AR-15 Bolt Carrier Tilt

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MSG Joe Carlos (ret.) discusses AR-15 bolt carrier tilt and its effect on accuracy.
Contact Joe Carlos directly at NCC1701 at penn.com

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3 окт 2024

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Комментарии : 95

@FTW1013 7 лет назад

Please continue with your gunsmithing tips and advice, it has changed my AR15s completely. Thank you sir!

@mariontinsley8646 2 года назад

Remember, MSG Carlos is speaking to long range accuracy shooters only in this video. For tactical and hunting use , anti-tilt buffers are great on helping you keep your rifle on target for a quick follow up shot if needed. When using an anti-tilt buffer on the range or hunting I dont experience much barrel movement when firing the weapon and pretty much stay on target.

@FUNshoot 2 года назад

Great point! Yes, this build advice is primarily for precision and long-range competition use of the AR-15.

@ghimmy47 Год назад

OR you can get a Patriot Ordinance Factory buffer tube. No more tilt. Got to admire this man's attention to precision detail.

@FUNshoot Год назад

Thanks! The options here are not exhaustive and your recommendation is a good addition.

@ghimmy47 Год назад

I wasn't specifically going for accuracy. The AR was a gift for my wife. I wanted easy, inline recoil and got it. The gun is strangely stable with a JP flash hider clocked correctly and a silent captured spring. BTW, I've watched my daughter shoot at dusk and can see no flash. I used an Osprey Defense piston that I think is history now on a starting point of a Ruger AR556. An additional "feature" of the buffer tube with a lip is I was able to shorten the buffer detent tip because the captured spring (although it can slide out) won't act like a standard buffer and spring and come out to be a mess. The castle nut is no longer a factor as the detent in the slot of the tube lip doesn't allow the tube to rotate. I just snug the castle nut up. POF even has a AR-10 buffer tube with 7 positions that works on my old Armalite (Eagle Arms) AR-10b. It's a short tube and uses a rifle length spring (weird). Because the BCG of that rifle weighs 20oz I selected an H2 buffer and got lucky. With the JPFH it's just as stable as the Ruger. I'm a little suspicious of the POF roller bolt cam but do like it. The AR-10 has some upper receiver wear and I wanted to negate that. POF has a roller cam that just drops in. On an AR-15 they have a combo of gas key and bolt cam, but I found there's enough meat on the lower left of the existing key to make a judicious dremel "quarter moon" just big enough to drop the cam pin past without weakening the gas key in any way. I used a Pacific Tool & Die with abrasive to square the front of the upper receiver. It's a solid tool.

@Mr1gun 3 года назад

POF has a anti tilt buffer tube (receiver extension) that extends around & past the buffer detent & under the carrier at rest.

@FUNshoot 3 года назад

In his articles, Joe Carlos went over the methods he's done extensive testing. Send an email to American Gunsmith if you'd like a personal response. americangunsmith.info/

@Mr1gun 3 года назад

@@FUNshoot Thank You.

@mr.lovell3645 10 месяцев назад

I am using this in my piston rifle (Ruger sr556) and it has helped my carrier tilt and dare I say removed it ... I have also used Aero Precision enhanced buffer tube in other di guns and it's good, pof is better...I think I used PWS buffer in the Ruger now that I'm thinking about it... Too many builds and parts 😂

@sladeoriginal 3 года назад

I will be sure to bring my feeler gauges into the armorer's room because I visit there so often.

@daveware4117 4 года назад

Your videos are interesting to me not really because im trying to accurize my ar-15. Personaly, i think my guns can already out shoot me givin good ammo. I just like your videos because it helps me understand the weapon more(alot more). I think theres way more to a rifle than just being able to feild strip and clean it. You touch on alot of that last 10 percent of knowledge about the ar-15.

@longerino 2 года назад

* a lot

@jimallison6292 5 лет назад

Love your videos keep them coming we cant get enough .

@FUNshoot 5 лет назад

These videos are an overview of articles from the author published in American Gunsmith americangunsmith.info/

@_Epictetus_ 4 года назад

Come back to us!

@wideopenyamaha 2 года назад

Works great. Thanks Joe

@FUNshoot 2 года назад

Great to hear!

@wideopenyamaha 2 года назад

@@FUNshoot he built my service rifle upper and it changed the game for me.

@checkpoint3260 6 лет назад

I like this kind of vid... and that kind of shop

@Shnick 3 года назад

Could a person machine a lip in the front of the buffer to fit the hole in the back of the bcg? Wouldn’t need much really. Of course, I had to type that prior to 11:15...

@freedreaming2482 4 года назад

Have looked into the POF. anti tilt enhanced buffer tube? It supports the carrier so it maintains alignment of BCG.

@FUNshoot 3 года назад

In his articles, Joe Carlos went over the methods he's done extensive testing. Send an email to American Gunsmith if you'd like a personal response. americangunsmith.info/

@robertbogan225 5 лет назад

What if they made a extended fluted barrel nut that could brace up aginst the cut in the barrel? That way the entire chamber and throat of the barrel is supported?

@FUNshoot 5 лет назад

Robert This is Joe Carlos answering. I authored an article in "The American Gunsmith" on match bolt carriers and another on Combating Bolt Carrier Tilt. I also made a video on carrier tilt for the "American Gunsmith". I am having difficulty visualizing what you are suggesting. You speak about a "cut in the barrel" but I am unaware of any cuts in an AR barrel. The only ways that I know to combat carrier tilt are to build up the front of the carrier (making it fatter) or to do something to support the back end of the carrier like the "Anti Tilt Pads" that I described in my article. The most efficient method is to combine both together. You may well be on to something that I am missing. Perhaps a hand drawing would help if you have the time. My direct e-mail address is NCC1701 -at- penn.com and you can feel free to contact me directly.

@dontask8979 5 лет назад

The nubs moving with the carrier may work ok, but nubs in the upper I think would work and last longer. As soon as the carrier moved back 1/8"~ the nubs wouldn't even have contact with anything.

@JamesSmith-su3oz 5 лет назад

Mr Carlos Sit you have sparked my intrest on this tilt problem, I'm a fal fan so I know what you are stating is true but could this same mod be used on a LR 308 or AR10? and has it, the mod ben tested? Thanks for sharing the wisdom.

@desert08glider Год назад

May. E a stupid question but what is the possibility of using a small weld, in a straight line from front to back, to build up those 4:30 and 7:30 spots then milling them down to an appropriate height? Is there a danger of metal failure in the carrier? I am thinking of a low voltage MiG type welder, say 140 gas shielded.

@FUNshoot Год назад

The rationale of threading and tapping the carrier to use a screw is to allow for easy adjustability. A properly-sized weld could accomplish this but any adjustment would be much more difficult, obviously. He describes his procedure in depth in his articles.

@allendiaz5176 Год назад

@@FUNshoot ah, I see. Another question then. How often would you figure the screw would need adjustment once set correctly the first time? Would the screws take a lot of wear? Are we talking about having to reset the screws after each use?

@robertosborne1753 3 года назад

Quick question; I can't find anyone that can show me any accuracy advantage by using a YM bolt and bolt carrier. Can you help me understand a little more the advantages of using this bcg please? I'm still wanting to wring out every last advantage on this match rifle build. Thanks.

@FUNshoot 3 года назад

This was discussed at length in the article series published by Joe Carlos in American Gunsmith.

@JohnProph 3 года назад

I definitely dont understand it because once the bolt is locked forward, who cares how it got there??

@BStott 7 лет назад

Mr. Carlos, you show how the thought is a carrier tilt will not align evenly to a cartridge and a barrel. However, you do not seem to recognise the design and operation of the bolt lugs engaging and locking into the bolt extension. This will not allow the tilted condition you describe between the bolt face, the cartridge and the barrel. With the bolt locking into the barrel extension recognised. What is another reason for your alteration providing some additional rifle accuracy through eliminating bolt carrier tilt? Thank you.

@wardo5415 7 лет назад

B Stott not only that, the breach has the cartridge centered perfectly with the barrel, assuming drilling was done properly. In theory, you could bring the cartridge in the breach at any angle and it would make no difference in accuracy, only sight realignment because the rifle is not moving on axis.

@LRRPFco52 6 лет назад

Self-loaders require slop to work. You can't have an interference fit with the bolt lugs and the extension, otherwise the gun would lock up. Everything you've though of, this guy has been looking for solutions for over the past several decades. Instead of just adopting a technique, he actually has tested them over fleet samples of rifles to prove or disprove their worth. Chambering is something else not discussed in depth in this video, but is something armorers like this have dealt with for ages.

@bradreeder7635 6 лет назад

Thanks for pointing that out. I was thinking the same thing.

@joecarlos2409 6 лет назад

Bolt lug lock up inside the extension is not as firm or true as many might think and this can be demonstrated in at least 3 ways: #1. Take a fully assembled AR-15 and clear it, place it on SAFE, point the muzzle in a safe direction and allow the bolt to go forward into battery on an empty chamber. Leave the ejection port open and watch the carrier as you slowly insert a charged magazine. Normally just as the mag. locks up you will see the forward section of the carrier move up in the receiver. So you have changed its position and in turn the orientation of the bolt face to the center axis of the bore. #2. Remove the magazine and double check that the chamber is still empty and then shotgun the rifle. Place a finger on the back of the carrier and attempt to move it up, down, left, and right. You will observe a large amount of movement. The position of the bolt face is changing with each movement. #3. Now if you really want to shake your faith in the firmness of bolt lock up take an AR barrel by itself that is not attached to an upper receiver. Hold a full carrier assembly in one hand and with the other hand grab the front of the bolt and pull forward all the way till it stops. Line up the carrier key with the pin in the barrel extension and you should be able to push the bolt forward with the bolt lugs passing thru their respective cut outs in the extension. Continue to push and the bolt will rotate and lock into position. The forward movement will be stopped when the front of the carrier contacts the rear of the extension. Place a finger on the cam pin to prevent the carrier assy. from unlocking and try to move the carrier left, right, up, and down and you will notice an enormous amount of movement! It is important to remember that these are gas guns designed to operate reliably in dirty battlefield conditions. To achieve maximum reliability and consistency in lock ups I recommend the use of a chamber brush near the end of each cleaning session. The videos that I do are all condensed versions of articles I have written for "The American Gunsmith" magazine so for better understanding I recommend reading the full text. I didn't invent the notion of bolt carrier tilt. It was a known shortfall to AR accuracy all the way back to Stoner's time. I have offered a well researched solution that will tighten your groups by an average of 14% which is significant. It is interesting to note that since my full article was published and the follow on video was circulated at least 3 custom AR-15 factories have incorporated Anti Tilt Pads in their carriers. I can't say if this is just "marketing" or if they performed their own independent research. Sorry this reply is so long but this is an involved topic. If you wish to discuss it further you can feel free to contact me directly at NCC1701@penn.com

@joecarlos2409 6 лет назад

We are dealing with two misconceptions. The first is that the lock up of the bolt lugs within the barrel extension is really tight allowing no misalignment of the cartridge inside of the chamber. I dealt with that previously and will deal with the second misconception now. All gun chambers have slop and that is needed for function. If the chamber was cut to the size of the loaded cartridge function would be impaired. So chambers have some slop in them and that varies quite a bit. In general, gas guns tend to have a little more slop, especially in guns such as the AR-15 that were developed as battlefield weapon designed for reliable function in dirty conditions. Slop in chambers limits accuracy because ammunition can position itself differently from shot to shot and one bullet may enter the chamber at angle from the right while the next shot may orient from the left, up, or down. We gunsmiths have some LIMITED control over this by our selection of reamers. We can limit chamber slop in the main body of the chamber by selecting (or having built) a reamer with tight dimensions in this area. Since the main body of the cartridge offers a lot of surface area to the chamber most of us try not to get carried away with chamber tightening in that area as all that surface area will just add to drag and friction resulting in function issues. More popular among gunsmiths is to tighten the neck area of the chamber (a little). This has much less surface area so it is more practical and has less tendency to negatively impair function. Still if we get too carried away....... On top of that different makers of brass vary brass thickness. So a chamber designed for thinner Lake City brass may be too tight for thicker Lapua brass. Decades past shooters, gunsmiths, and handloaders pretty much came to agreement that proper loading techniques can trump tightening of the actual chamber with less function impacts. You are probably aware that bench rest shooters and participants in certain competition events like Match Rifle, Palma, and F-Class sometimes just neck size (and shoulder bump) their brass during processing. To do this the shooter must be working with brass previously fired in their chamber. As you know when that brass was originally fired it expanded (obturated) out to the walls of the chamber to a perfect fit. Once the pressure was relieved the brass "sprang back" about .001" giving just enough clearance to reliably re-chamber after being reloaded. I experimented on the machine rest with this technique of only neck sizing and found it very effective in the AR-15 for single fed slow fire events. Average reduction in group size was an impressive 16% which is well worth the effort. Reloads for rapid fire events where rounds are magazine fed are still loaded using full length sizing dies, however. The accuracy improvement with the neck sized reloads is due to the superior fit of the body of the casing resulting in bullets being better aligned with the bore. As I was conducting my tests I wondered how much oversized my chambers were. I found quite a bit of variance. I would measure the body of a factory new round before firing and then pick it up after firing and remeasure it. I found this second measurement to run from .003" to .007" fatter. (You can employ this same technique to determine how much oversize your own chambers are.) That is roughly the thickness of one to two sheets of paper and is a big deal to accuracy! I did not use any 5.56mm NATO chambers in the study and imagine they might be even fatter. The conclusion is that the fit of AR-15 chambers to full length sized or factory new ammo is not hand and glove and there is more than enough slop to cause negative impacts to accuracy. Bolt carrier Anti Tilt Pads result in rounds being better aligned to the bore in these fat chambers resulting in an average 14% reduction in group size. Sorry this answer is so long but these are involved topics. If you wish to discuss them further please feel free to contact me directly at NCC1701@penn.com Thanks

@tengu190 4 года назад

No mention of anti-tilt buffer tubes?

@FUNshoot 4 года назад

In his articles, Joe Carlos went over the methods he's done extensive testing. Send an email to American Gunsmith if you'd like a personal response. americangunsmith.info/

@jeffgilkison6170 6 лет назад

Joe, When adjusting the screws to uniform the gap at the rear of the bcg should you just try to even the gap around the bcg or should you adjust to make the bcg parallel with the bore axis? Say, for example, your bcg is way undersized and adjusting the tilt to get a uniform gap in the back actually imparts a forward tilt on the bcg. Would it be more beneficial to monitor the gap up front to keep the bcg parallel with the bore, and how would you accurately measure the front gap (especially with the barrel installed)? Thanks, Jeff

@joecarlos2409 6 лет назад

Jeff I know of no way to measure the gap around the front of the carrier with the barrel in place. So I simply use feeler gauges at the back to achieve an equal amount of gap between the top and bottom of the tail end of the carrier. With the pads located at 4:30 and 7:30 on a 12 hour clock face most of my carriers level out with about .035" of the pin head above the surrounding surface. Then I use red Loctite and stake the screw heads. It is important not to get hoggish with your adjustment. A carrier that it tilted up at the back is as bad as one allowed to tilt down. You want it level and the best way I have achieved that is with the feeler gauges. I suggest reading my full article in the May, 2017 of the "American Gunsmith" as these videos are very condensed versions. Feel free to contact me directly with any additional questions NCC1701@penn.com Joe Carlos

@keithbittner2172 5 лет назад

@@joecarlos2409 hi Joe, I viewed three of your videos on barrel harmonics and bolt tilt. You have taught me much and confirmed some things that I had thought about. I found your solution for bolt tilt to be very interesting, in fact I never had thought about that but now I do. A thought you might find to be successful would be to locate, drill and tap a through hole vertically in the rear hold down lug. Insert a properly sized set screw that would push the carrier up and that set screw would also keep an equal clearance laterally by riding in the bcg buffer retention pin grove. Alternatively, a similar method could be used at the back hold down pin . Should you ever try this I would love to hear about it. Good luck in your craft. Keith bittner

@m.s.l.7746 6 лет назад

So you replace a nice long & smooth contact (ski) with a rough little bump (head of a screw) that is going to cause variations in bolt velocity & resistance between shots... Not only that, it's going to damage your upper & receiver extension.

@joecarlos2409 6 лет назад

Skepticism can be a good thing. But that needs to be backed up with actual range test firing. So when I began trying to come up with a solution to bolt carrier tilt I got out from in front of the computer and hit the test range. I could clearly see improvement in my groups right from the get go. I kept good records as well. During my range testing I changed only one variable, the carrier. I fired groups with the same brand of carrier as it came from the manufacturer and then fired a second group with a carrier equipped with Anti Tilt Pads as described in my video. Groups were fired with the same lots of match ammo in dozens and dozens of different uppers. When I analyzed the data I determined that the groups fired with carriers having Pads were on average 14% tighter than the same brand of carrier without Pads. I don't know if you have ever participated in competition but I did so extensively and when I was on the circuit I would have killed for 14% tighter groups especially when using the Pads is a cheap solution and seems to have no downside. You state that the Pads will damage both the upper receiver and the buffer tube. We are not seeing either. I have had these modified carriers in circulation with active competitors for years now. Not too surprising some of these folks have shot out (figure around 3,000 rounds) their original barrel and sent their uppers in for a new barrel. When I get one of these back in the shop I put a good bright light with a magnification lens on the back of the receiver. If I look really, really close sometimes I can just barely talk myself into seeing a little "scuff" where the pads run. No real wear, however. I have one lower here that I use for all my testing. I suppose the number of rounds put thru it with carriers that have Pads in place is well into 5 figures now. No issues with the pads in my lower and none of my customers have raised concerns. I have a money back satisfaction guaranteed shop policy and to date no body has returned a carrier asking for a refund due to any wear or negative impact on groups. I do have an In Box full of messages from happy customers who were able to see group reductions due to the Pads. I don't claim that my approach to combating the accuracy robbing influence of bolt carrier tilt is the "end all or do all". I said right from the get go that my efforts are what I consider "baby steps" and that I hope that some smart guy will improve on my design. I would be very happy if that smart guy turns out to be you or someone else reading this reply. If you want to start out by testing my design my e-mail is NCC1701@penn.com. Remember, there is no risk to you or anybody else because if you aren't happy I will gladly take the carrier back and refund your money. Thanks for your interest, Joe

@joecarlos2409 5 лет назад

@Viscous Shear Mr. Shear I mostly work on National Match, Palma, and F-Class firearms and shooters in those events don't normally use AR's with piston systems. Therefore, I do not have the experience with piston guns to address your concerns. Sorry, Joe Carlos

@eugeneanderson8706 7 лет назад

Have you tried the DS Arms bufferloc? Got one on my rifle with the Sharps Rifle Company bcg. Compared to a standard milspec, it has a slightly larger diameter in the rear and along with the bufferloc, I have consistent travel and wear when going back and forth, corrects the tilt real well. A lazy man's way to level the bolt carrier I think

@joecarlos7790 7 лет назад

Mr. Anderson When the folks at DS Arms first came up with the unit you describe they advertised it briefly in "Shotgun News" and I saw it. I am all about easy to do drop in parts so I called them up. At the time they were only offering the unit in a carbine length buffer. I asked them if they intended to include a full length buffer at some future date for use in standard length buffer tubes. They said they wouldn't be offering a full length buffer. Most of my customers are National Match bullseye shooters who use full length buffer tubes. So, I am sorry, I have not tested the DS Arms unit.

@bsracer85 8 лет назад

Mr Carlos, Tried to drill and tap my carrier. Man the steel is so hard I could not scratch it. Tried to spot heat with no success. Do I need to put the carrier in a furnaces to anneal it? Looking into some carbide bits. What size button heads did you use. 6-32? Any advice is appreciated.

@joecarlos7790 8 лет назад

Sir: You are right about the hardness of some of these carriers! YES, carbide bits are a MUST! I use a 5-40 button head cap screws and countersink the heads a little (1/4" diameter on that hole). My e-mail address is NCC1701@penn.com if you have any more questions.

@peeeoii2738 8 месяцев назад

Carbide for heat treated steels HSS is really only good up to 54 Rockwell make sure your rpm is set right center drill before drilling use tap magic and clear chips keep pecking don’t just drill through.

@tkeefe0601 2 года назад

First off thanks you for sharing your wealth of information with us! I've been going through all of your videos. I thought you looked familiar and I think perhaps I ran into you at camp perry back in '03-'06? I have one question on this. Have you tested the impact of the lift the carrier gets from having a magazine inserted? Seems like the magazine could both reduce carrier tilt and also potentially push the "enhanced" bolt you're proposing up too high to where it's no longer aligned? I was fiddling with my large frame AR and there's quite a noticeable lift to the bolt carrier when the mag is inserted with or without rounds in the magazine.

@FUNshoot 2 года назад

From Joe Carlos. I have been studying the influence of magazines on the AR for decades and have been reporting on those studies in American Gunsmith, available to current subscribers. americangunsmith.info/subscribe/ Magazines have a huge vote in the performance of Stoner Platform rifles. As you have observed, there is so much slop in the size of the "bore" of the upper receiver and the carrier that magazine pressure on the underside of the carrier moves it up. Different magazines evidently exert different amounts of lift. This can cause variations in downrange Point Of Impacts. I reported on this in an article titled, "Magazine Checks" in April of 2015. As you point out, these same magazine pressures likely interact with the carriers relative to the tilt that I wrote about in another article titled, "Combating Bolt Carrier Tilt" published in May of 2017. That said, however, when I was trying to find solutions to tilt I did shoot a number of AR-15's employing a variety of magazines in the machine rest. The average improvement in group sizes was 14% using the Anti Tilt Pads on the bottom rear of carriers. Customers who have purchased carriers from me with the Anti Tilt Pads have no doubt also used magazines with varying degrees of lift. Many of those customers have written to me describing improvements in group sizes. So the conclusion I arrive at is that the lift that magazines provide is not an adequate solution to bolt carrier tilt. The various parts of the Stoner Platform do interact with each other as this carrier/magazine discussion points out. You can't "fix" AR groups by only concentrating on one part of the rifle. You have to improve many parts and take into consideration their interactions. The subject of bolt carrier tilt and magazines was covered in at least one other article I wrote for the magazine which was titled, "AR-15 Fliers". This started in Feb. of 2021 and went for 3 months. Some gas gunners think that the only way to shoot an AR is to fill up a 30 rd. mag. and proceed to empty it in the general direction of the target. Serious National Match Course (NMC), F Class, and Palma AR shooters actually use single shot mags. called "Bob Sleds" that have NO spring or follower and only shoot one round hand fed one at a time thru the ejection port. These Bob Sleds exert NO upward pressures on the bottom of the carrier and are my go to choice in slow fire events. If you are interested in reading more on the above topics email me directly at NCC1701 -at- penn.com. Thanks for your interest and observations.

@tkeefe0601 2 года назад

@@FUNshoot Thank you for your reply! I had thought that perhaps given your context single round loading would be something you'd be considering and I would imagine adding the pads to the carrier would greatly improve consistency for that purpose. Seems like the only way to really eliminate any potential tilt in all use cases would be a much tighter fitting carrier/receiver channel, but I would imagine that would come at the cost of reliable cycling of the action.

@Not_Andrew_Huberman 6 лет назад

The spring pushes the bolt into the extension. Flat surface on flat surface.. no tilt

@5jjt 2 года назад

Accuracy measurements were 8.8% better after the anti-tilt modifications.

@treybadd 4 года назад

Mr. Carlos, have you seen the Lantac enhanced bolt carriers? Do they align the bolt carrier like your modification does?

@FUNshoot 4 года назад

From Joe Carlos. I have tested the Lantac carrier and found it to be no better than conventional carriers. There is not enough build up on the bottom rear of the Lantac to raise it up enough to be level in the upper receiver. Unfortunately, it still tilts the back of the carrier down which throws the bolt face at an angle to the bore of the barrel.

@treybadd 4 года назад

FUNshootVideo Thank you for the response Mr. Carlos. That is exactly why I asked. It didn’t seem like enough.

@treybadd 4 года назад

Have you ever experimented with the Harrel tunable comp/brake?

@FUNshoot 4 года назад

@@treybadd Yes. See the October 2016 and June 2018 issues.

@treybadd 4 года назад

@@FUNshoot Mr Carlos, do you have an email you can share so I can contact you?

@ung427 4 года назад

I notice that when I close my rifle with the bolt carrier inserted it goes up in the upper receiver right before closing it lessening the gap between the upper receiver and the bolt carrier, this seems to be due to the springed buffer tube pressing onto the back of the bolt carrier and righting it in the receiver. How much does this stop carrier tilt? It seems like it would stop carrier tilt as much as the back of the bolt carrier is trued to 90 degrees.

@FUNshoot 4 года назад

"Combating AR-15 Bolt Carrier Tilt" in American Gunsmith covers this in detail.

@voodoo1449 5 лет назад

So if my bolt is not perpendicular to bore because the back of my bolt carrier group is being held down by gravity, in theory, I should be able to shoot my AR upside down and it would be more accurate.🤔

@Not_Andrew_Huberman 6 лет назад

Yeah there's buffer tubes for that

@m.s.l.7746 6 лет назад

Also, you do realize that the bolt is "floating" in the carrier right?

@Physics072 3 года назад

It has no impact on accuracy. When you shoot the gun the bolt is LOCKED non moving it cant tilt. By the time its unlocked the bullet is gone. The tilt can affect wear patterns on the buffer tube but no effect on shooting.

@FUNshoot 3 года назад

If that's your tested experience, write it up for American Gunsmith. Author Joe Carlos documented his tests based on results from 160+ rifles built for ATC competition by a major military team.

@Physics072 3 года назад

@@FUNshoot Link me to the data of the 160 rifle testing please.

@5jjt 2 года назад

Seems like sound logic, but I don't suppose this man would go to great lengths to drill hardened bcg's unless he found/tested accuracy. I believe he stated, "8.8%" improvements.

@StuninRub 9 месяцев назад

@@5jjtHe's a salesman.

@Hornet135 2 года назад

Upper/lower fit has no impact on mechanical accuracy.

@FUNshoot 2 года назад

True for typical, as-issue rifles. However, machine rest testing indicates it has a small but measurable effect, usually only of concern with precision/competition rifles. Mr. Carlos has published his findings in American Gunsmith about this.

@StuninRub 9 месяцев назад

@@FUNshootThen his testing methodology is shit.

@deeremeyer1749 6 лет назад

Do you really know how ARs actually FUNCTION? The BCG doesn't "tilt" as it cycles because its not being pushed rearward/tilted "up" by the gas tube/gas key "interface". Gas goes INTO the "expansion chamber" of the BCG where it EXPANDS and pushes the body of the BCG "straight back" because the BOLT IS STILL "LOCKED" IN BATTERY IN THE BARREL EXTENSION. When "unlocking" occurs as the "cam pin" rotates the bolt within the BC, the BC pulls the bolt the rest of the way out of the extension and takes the bolt with it as it "cycles". As for "loose fits" between uppers/lowers and barrels/receivers, I suggest you find better parts and maybe invest in a good BARREL NUT "SOCKET" AND A GOOD TORQUE WRENCH because if you've got "play" at the barrel/upper "interface", you've got BIG problems. And a "loose fit" between "upper" and "lower" has ANYTHING to do with accuracy/precision when the UPPER is the "entire rifle" and carries the SIGHTS/SCOPE, BCG AND BARREL and no "play" between the upper and lower is going to "throw off" any part(s) of the upper assembly. The primary reason "AR-15s" when built to "mil-spec" aren't "accurate" and/or "precise" is because their "open sights" aren't exactly "ideal" for "offhand" shooting and they tend to be pretty "coarse" in their adjustments and getting them "dialed in" requires adustments to both the FRONT SIGHT POST and rear elevation/windage adjustments. I do believe SOME "service rifles" are also equipped with "MIL" sights. And a "MIL" is 3.6" at 100 yards while an "MOA" is well under ONE THIRD OF ONE "MIL". Meaning "MOA" adjustment/calibration sights/scopes can be "dialed in" more than 300% "better" than "MIL" sights/scopes when a "click" is either "1 MOA" or "1 MIL". Even if you got to "1/10th MIL" you're still moving POI roughly 40% more per "click" than with "1/4 MOA" adjustment increments. As for "high-end" ARs and their "accuracy guarantees" from manufacturers like Les Baer, if you're willing to pay $2500-$3500 for that "1/2 MOA guarantee" and think its being achieved with "special" parts rather than simply taking advantage of the "inherent accuracy" of the AR "architecture", knock yourself out. I own a Les Baer Premier II Tactical 1911 with the 1.5" @ 50 yards guarantee and that pistol will do what it's supposed to do with even "cheap" cast 200-grain SWCs I cast myself from range scrap lead and just a little time and care in handloading "varmint" ammo with them. But I've also got a PAIR of "AR-15s" with 18" Wilson Combat Stainless "Match" barrels with one in 5.56x45 and one in 7.62x40WT and BOTH are WAY sub-MOA with nothing but "cheap" uppers and lowers, Timney 3-lb. comp triggers, full-float tubes, Magpul STR stocks and "throw together" reloads using Hornady V-Max bullets. I'm pretty sure 10 rounds in right at an inch at 100 yards MULTIPLE times with a "cheap" home-built "AR-15" I put a whopping $1200 in and "built" in a couple hours proves that "Stoner" knew a hell of a lot more about what he was doing and why than you do. Hell, it doesn't TAKE a "gun genius" to see the "inline design" of the AR barrel/BCG/buffer tube/stock ALONE is "common sense" for getting "accuracy and precision" out of a supposedly "loose" rifle design with parts ONLY "pinned together". And by the way, the ORIGINAL "AR" was the AR-10 and he certainly didn't intend to have "his baby" in .308 Winchester/7.62x51 NATO get "outshot" by M14s and M1 Garands. I've got an "AR-10 clone" as well as my aforementioned "AR-15s" and it sure shoots nice for a 16" "carbine" that cost me all of $1100. DPMS "Oracle". Its ALSO "way sub-MOA" and even with FMJ ammunition my "AR-15" in 5.56 doesn't "like" at all. There's one other "small issue" with mil-spec "ARs" of the 5.56x45 NATO variety that has a negative effect on "accuracy" and "precision". Chrome-lined, hammer-forged barrels. Great for "long barrel life" but chrome plating just doesn't "lap" worth a damn and since its applied post-rifling (duh) its pretty difficult to get a "match" barrel dunking and plating barrels in a "electrolysis" tank. Pinned front sights, non-floating handguards, "pencil" barrel profiles etc also don't do a lot for "service rifles". Neither do close-minded "gun experts" shooting them in "competition" and getting into "ARs" with a whole bunch of preconceived notions and "conventional wisdom" about them that is mainly pure b.s. If you expect "crappy" accuracy/precision from a rifle you're almost certainly going to get it. Especially if you're a "90-grain boattail" guy trying to make a "service rifle" shoot bullets it wasn't remotely designed/intended to shoot well and insist on stacking the ENTIRE deck against yourself instead of just MOST of it.

@joecarlos2409 6 лет назад

You obviously spend some time reading books and scouring the Internet for videos on the Stoner Platform. Book learnin' is a good thing but if one really wants to understand the rifle at some point you have to get out from in front of the computer and either employ the thing in real combat on the battlefield, shoot it in competition, or perform tests with it. I have done all three but will describe to you the testing performed prior to writing the article I published in The American Gunsmith on "Combating Bolt Carrier Tilt" or the making of this video which is a condensed version of the article. Before I detail how I tested the Anti Tilt Pads I must comment on your first paragraph, however. In it you appear to paraphrase something you read from a book on the unlocking of the bolt. It is not the unlocking of the bolt that we are concerned with in respect to bolt carrier tilt. It is what occurs just prior to firing the round when the carrier is at rest. The back of the carrier is down (sometimes even to the point of resting on the bottom of the receiver). That causes the bolt face to be at an angle and the round in the chamber to be also at an angle to the bore. Readers just joining the conversation can see this bolt carrier tilt by opening their gun safes and taking out and inspecting a couple of uppers. Contemporaries of Stoner way back about 50 years ago recognized that this carrier tilt was a design flaw with respect to shooting tight groups. Old time gunsmiths of the era silver soldered shim stock in long strips on either side of the bottom of the carrier. Eventually some of these Pads came loose and jammed up the guns and that idea was dropped. Gunsmiths collectively stuck their heads in the sand for decades and pretended that the problem didn't exist. When I started to experiment with solutions years ago I had already learned from those old time gunsmiths to avoid the silver solder approach with strips of shim stock. I chose instead the idea of the cap head screws. Because of their small domed heads only the very top of the curved head makes any contact with the inside walls of the receiver keeping friction to a minimum. There is not much pressure on the dome heads so you only need a little contact surface. As soon as I started shooting groups with the pads in place I saw groups tighten up. So every gun that came in my shop for nearly a year got tested with a true match carrier of the same manufacturer without Pads vs. an otherwise identical carrier with Pads. Dozens of test firings with the same lots of match ammo but no other changes. At the end of the study I ran an average of the group sizes and found that those with the Pads were 14% tighter than those without. I don't know if you have ever shot in competition but I have done so extensively. When I was on the circuit I would have killed for a 14% reduction in group size at so little $ cost and with no downfalls. Lots of competition shooters are using my carriers with the Anti Tilt Pads and I have an In Box full of thank you notes but no accuracy complaints to date. As I was closing the article I mentioned in "The American Gunsmith" magazine I stressed that my efforts should be only considered as "baby steps" and encouraged other gunsmiths to come up with their own designs and ideas to improve on my work. Perhaps you will end up being the person to invent a better mouse trap. If so I will be the first to congratulate you. A word of advice, however: I suggest you perform your due diligence by doing a lot of testing on the range before sitting down in front of the computer to write an article or post something on the Internet or before jumping in front of a camera. Otherwise, I doubt you will have a leg to stand on. Good Luck! Joe Carlos

@longerino 2 года назад

"accu wedge" or whatever he said is just a little bit of rubber.

@longerino 2 года назад

does not work with piston driven AR's DI only.

@FUNshoot 2 года назад

Yes, and testing indicates the Accu-Wedge (or Accurizing Wedge) is helpful.

@FUNshoot 2 года назад

@@longerino Joe Carlos only used internal piston AR-15s (commonly and wrongly called DI/direct impingement) in his testing as that is the basis of Stoner's original design, most commonly used in issue rifles, and exclusively used in Service Rifle.

@deeremeyer1749 6 лет назад

M14s are "difficult to work on"? How so? And how would anybody design a rifle for the U.S. military and presumably knowing that U.S. military doctrine has always been to focus on accuracy over "rate of fire" (as evidenced by the fact that the vast majority of M14s were semi-auto with only "select fire" M14s being used as "BAR replacements" as a "light machine gun" with a few per unit being "issued") go about designing it for "ease of service" in the field? Common sense is that the better a rifle is made the more accurate and precise it should be. The more accurate and precise it is the fewer rounds should be needed to "hit the target" and "take out" the enemy. Fewer rounds fired means less wear and tear and fewer malfunctions and failures and fewer necessary "field repairs". Not to mention that even the Korean War was far different than World War II in that troops weren't just dropped on a beach to invade and march and fight across some foreign country. The move toward troops "riding into battle" instead of "marching into battle" was well underway and that's where "air-mobility" came from as first used on a widespread basis in Vietnam. The days of troops spending weeks or months or even several days "in the field" were over for a number of reasons. Not least of which was that there weren't too many "armies" who had any doubt that fighting that kind of war against the U.S. was going to end badly for them. Regardless, whether he "wanted" or "intended" to or not, when Eugene Stoner designed the AR-10 (lets not forget THAT rifle was/is the "original AR") he certainly did design a very accurate and precise rifle when its not "handicapped" by chrome-lined barrels, heavy and non-floating handguards, improper or imprecise manufacturing, worn-out parts, etc.

@FUNshoot 6 лет назад

>> M14s are "difficult to work on"? How so? Compare the cost of a National Match M1A/M14 to a National Match AR-15/M16. A competitive AR-15 is about half as much. Gunsmiths in the know find the AR-15 easier to keep running at match specs. Nobody that is competitive in ATC Service Rifle chooses the M1A/M14 anymore.

@AtroposLeshesis 3 года назад

How does this have anything to do with accuracy. As far as I know a rigid connection between the barrel and upper receiver is the only thing that effects accuracy besides the rifling , chamber, and the crown. Having a bolt carrier that tilts wouldn’t effect those things at all. The bolt and barrel extension are the only parts interacting with the barrel. Now I know why you said you “were” a writer for a magazine.

@FUNshoot 3 года назад

>> Having a bolt carrier that tilts wouldn’t effect those things at all. What tests did you perform to make that the determination?

@StuninRub 9 месяцев назад

@FUNshoot What test have you performed that weren't based on pseudo fudd confirmation bias?