Thank you so much for all the detailed explanations you provide for some of us would like to know all the nuts and bolts and what goes into all the aspects of reloading. You definitely hit the spot.
I can’t express how pleased I am that I found your channel. The knowledge you provide has been invaluable to me as a new loader. The concept is vastly more important than any specific recipe. The why, promotes thought far beyond the how. Thank you.
I've long said that "neck tension " can't be defined by ID. Glad to hear it from someone else. I know years there are many variables that goes in to it. Glad to have the term friction interference now...never really knew what to call it.
Great video Greg. I have seen several folks that subscribed to the .002 philosophy with strange looks on their faces as the last cartridge in their magazine had either moved in the case neck, or in one instance, become separated from the case. As always, I appreciate your efforts!
Cmon man, tell us how you really feel! Seriously I used wonder what was happening to my seating depth when I drove over 3 miles of washboard gravel road to get to the range. It was that that sent me down my own path of experimenting with interference, ultimately resulting in major improvement downrange. Excellent vid!
Hey Greg! Thanks for the awesome video! What are your thoughts on the Lee Collet dies? Have you ever tested with them? Maybe use a body die to bump the shoulder, then the collet die for neck sizing? Thanks again!
Thanks for the video Greg! I’ve long wondered a better way to understand the neck tension dimension because it just doesn’t make sense as to why pressing the shoulder or neck down (sizing) creates measurable tension with different thicknesses and brass compositions… Interference fit seems to make more sense!
Very enlightening video. I also agree with the philosophy that even though you may have the same neck ID in each and everyone of your cases it does not equate to you having the same amount of force required to seat a bullet in each in every case .To become a good and proficient reloader you must take the journey and experiment with different variables that affect the outcome of your reloads.
I think the problem here is that most people don't come from a machining background and aren't sure what "interference fit" means . Also you can't measure an interference by distance, it needs to be measured buy pressure., Or some esoteric Newton meter reading😂
I know exactly how you feel. Lots of times I hear people say “I didn’t do nothing”, we know what they mean, but what they’re actually saying is “I did something”.
I also anneal my brass everytime. An old bench rest shooter told me about the Lee Factory Crimp die. I'll use a medium crimp, 2 pulls on the press rotating the cartrige about 180 in between and that has really helped my accuracy and shrank my group size down to ragged holes at 100 yds
Generally speaking how much seating force do you see on the AMP press when seating your bullets? I’ll admit that I am probably running interference a bit loose but I typically see a value of 40 on my K&M press with a farce pack installed and it’s pretty consistent from what I can tell.
Let me start with...LOVE THE VIDEO!!! At 14:50 you talk about the relationship (or lack thereof) between diameter interference and bullet seating force. My brain calculates this...there IS a relationship between them, however, not a consistently measurable relationship. With that said, I'd be curious to see if the same lot brass, fired once, annealed, making an attempt to keep ALL things equal between the brass and the prep of the brass, using your nifty AMP press, would result in VERY similar seating pressure requirements. Just a thought. Thank you for making us THINK and for keeping us on our toes! GOD BLESS!!
When using an expander die, does it make any difference if you use a bushing die or not. If using a bushing die and separate expander die, does it really make any difference what size of bushing to use?
Great video, but I have a question. I am also using a SAC modular sizing die. You had mentioned that you are using a mandrel three thou below the O/D of the bullet. I was wondering, do you have a set rule for the size of the bushing, you use in relation to the mandrel? You mentioned the bushing, but I was not clear what you actually said about it. Also, did I miss it in the video, other than the “three thou under the bullet diam” you were able to achieve repeatable pressures on the Amp press? If you answered these, I apologize, I’m pretty old and a bit slow now at times. Thank you
I'd like to ask you what are the math you do to choose the proper bushing to ensure your mandrel work enough and his not just operating in the spring back. Is there formulas like the one we use in the aircraft industries with sheet metal? I never done anything with brass and cylindrical shapes. Like for example for a 6 Dasher. You would be using a 0.240'' mandrel and the brass neck wall thickness is around 0.01325'' (Alpha). Loaded it's around 0.2695''. What would be your calculation for figure out what bushing to order form SAC?
Redding uses neck tension terminology in their catalog which is where a lot of people get information from. For myself I’ve played around with different neck bushing sizes and found a sweet spot trying to error on a solid hold due to recoil when a rifle is magazine fed. Your spot on that the bullet only wants to be released as consistently as possible. Even a simple arbor press with a in-line seater gives you seating force feed back a AMP press is cheating. Now please layout your secret recipe for that ultra consistent seating force.
Glad someone finally said it, I agree completely. I use standard dies for my loading with a the supplied expander ball. I do trim and deburr the flash holes and turn the necks of my brass and sort by weight but that's it, I don't chase the lands either. My Savage in 6.5 Creedmoor shoots to 3/8moa or slightly less. Thanks for the advice on adjusting the dies to start to expand the neck while the tip neck is still in that portion of the die is genius. I'll run off 50 to see if there is a measurable group difference, I'm betting all things being equal there will be.
After thumbing in rice, how do you treat inside of the neck? Do you brush inside the neck to change bullet seating force? Would like to see your process.
Could you elaborate on the difference in process between your two examples? Also have you thought about addressing the common thought process of bullet runout and at what point it becomes an issue?
Quick question; you mention forster sizing dies. Can you tell me how to adjust neck interference fits with this brand? I only really see a REALLY limited selection of sizing balls for their dies. Anything?
That's because they didn't. By today's standards, if taken as the typical 1st place performance, the group sizes and scores shot in the 60's and 70's do not hold up to what people are doing today. What they were doing was still impressive given the equipment of the era, but there is no comparison to how consistently people shoot today. Even the average shooter can lay down performances that would have been considered supernatural back then. This also doesn't discount some of the extremely good groups/scores that were turned in, some of which are still impressive even by todays standards... but there can be no argument that those results are far easier to achieve today with the advancements in every area of this discipline.
@@primalrights I grew up in that time on the line's an benches with my family most of the places we traveled to back then are no longer there 22 hi-power center fire was the greatest next to the 24s seen some extremely good groups
I'm *missing* something here Greg. How thick are your necks and what are you using to cut them? 35-45 lbs of seating pressure is where I try to live as well but 0.003 will not get me that low. Maybe I just don't have a grasp on the yielding/spring back issue yet.
Have you found a range of bullet seating force that is generally desirable for consistent accuracy? I understand that this value could be exclusive to each set load of parameters, but is there a general area you're looking for when working up a new load? Thanks for all the content and knowledge you share!
@@primalrights And what do you consider a good range for peak force on the AMP Press? So say your average is 40 - how much up and down are you in general?
@@sf2189 Good results are typically +/- 2lbs, so if I have a total swing for 90%+ of the rounds that fall within a 5lb window, I'm good. Depending on how seriously I'm taking that ammo, I will accept up to a 10lb window. Anything outside a total 10lb low to high variance gets culled for certain even on ammo I'm not super concerned with.
Great video, very well explained. I got to the point where I run a crimp on my hunting rounds, benchrest rounds that get treated like a carton of eggs don't get crimped. I did it because some bullets in some hunting rounds definitely moved, I could never put it in words the way you did.
You made a passing comment on tumbling brass in rice, do you add any kind of polish or cleaning substance to the rice or is it plain rice. I've been using a rotary tumbler with rice but it doesn't seem to come out as shiny as what I've seen from you.
My God! Yes. I have been doing the "WORK", and you make complete sense. I have been thinking this since My data was not matching what " others " claim. Especially, when there are a few that make the claim the expanding ID, should be performed separately.
DUDE!! Thanks for this video ive been saying this to people i know reload for other people for profit ive never been comfortable using .001 diameter interference
Greg, You're provoking the natives.. You should have titled this video "The reason why everything matters" or "The need for knowing the true science and process of correct annealing to determine friction interference using your Amp press and Annealer" or "How hard is your brass? No, i'm not kidding.. really how hard?" etc... But you may have run out of space for these titles. I use a webster to test my annealed brass because I have not popped for the amp products that i must agree have revolutionized elite level ammunition quality and data driven process knowledge. You are a true renaissance man! I'm going to join your content supporters or make a visit for the full Greg experience, either way I'm sold! Thank you for the content!!
I am no math wizard, but if your mandrel is .003 under bullet diameter, that means if your interference is .005, then your brass is springing back another .001/side coming off the mandrel.
So, I'm not crazy after all😂. Every time I've heard/read about "neck tension" and then paid attention to the graphs of bullet seating force consistency, I always thought about the other variables that also require equal consistency prior to the bullet being seated! (Inside neck prep/lube, neck thickness/turning, chamfer/de-bur). Always seemed like it would be much more to it.
I’m curious in your early AMP Press chart, if all things were truly equal (dimensions, thickness, annealing, etc), do you know why you had one extreme outlier? There is obviously something different that isn’t fully understood. Do you just put those in the fouler bin and move on? Good video!
I agree with everything you said. However, we all need a place to start. We are not all FT shooters or gunsmiths with the time and budget to test everything. Nor can we all afford an amp press. .002 interference fit simply provides a good starting point for the hobby reloader like me. I have seen .003 recommended for hunting too. I found your old flame annealing videos. Are you still using that or an amp?
I need some help with seating force. 7mm08 lapua brass sac sizing die with mandrel. Tried 4 different sizes of bushings and i think i have 5 mandrels. My seating force is off the charts and i cant figure out why. Brass is amp annealed. Any idea what i can o to reduce seating pressure/force? Im heading out to the reliading room if anymore info is needed like sizes of everything.
@primalrights I will. Thank you. Also had a call into you for some stuff I ordered. Hope to see it soon. Yea I'm really pulling my hair out on this seating force thing
When it comes to this subject there are just so many variables I think the only thing you can do is just try your best to reduce the amount of variables with consistency. And trying to keep every Shot the same. I think it is almost impossible to eradicate every variable. But trying to minimize them, the best you can is all you can do.
I've found, using an AMP Press, sometimes I have to use an expander mandrel only .001" under or the same diameter (spring back) as bullet diameter to achieve around 30-50 lbs. of seating force and if I use a smaller diameter (-0.002", -0.003") mandrel, the seating force goes up as high as 125 lbs., which in my opinion is too much and could deform the bullet. Maybe not. I'm not sure what the limit is, but 125+ lbs. seems excessive. This varies from brand of brass and caliber, but I try to achieve a seating force of between 30 lbs. and 50 lbs. I have a 300 WSM F-Class barrel that performs better with around 80 lbs. of seating force. I'm not sure I agree with your assertion that using a .003" smaller diameter mandrel, across the board is necessarily sound practice.
That's because you're not thinking past step 1. How else do you suppose you can alter bullet seating force without changing expander diameter? Lots of ways. I can keep my expander at 3 thousandths under, and make my seating force whatever I want it to be. So I don't have to be wrong in one step, to get right in another step. I can be right in both steps. I'll have a video on that sometime.
This video was very informative. Just goes to show that no matter how long you’ve been handloading there are many things in your process that can be incorrect while you adamantly argue that they are correct. Looks like I’ll be placing another order with 21st Century to get the mandrels that are .003 under bullet diameter. Thanks for sharing your expert knowledge with rednecks like me. Please keep up the good work, I will certainly stay tuned.
Thank you for this video, you are spot on. Calling a diameter interference fit a tension is just stupid. It is a dimensional variable and has nothing to do with force directly. Frictional force is defined by a coefficient of friction (static or dynamic) times the normal force to the motion direction. Since most hand loaders can’t become development laboratories, it is natural to use the diametrical interference fit between the bullet O.D. and the brass neck I.D.. it comes down to the expense hole you wish to delve into versus establishing a very consistent processing of your components and their final assembly. I vote for the latter.
Just be like us long range black powder guys and just shoot unsized cases with no "interference" and then you don't have to worry about any of this. ;)
Funny.funny. Had this same conversation with myself in the mid 90s. I want a affordable way to read pressure, live data. Kind like hauling around a chrono or not.😊
lol now I have to check my Forster die bushing size and my 21st expander diameter :) although my ammo cant be "moved" not in the field, nor while competing.
SO FOR A GUY RUNNING A HEAVY FOR CALIBER BULLET IN A REAL WORLD FIELD APPLICATION.. IE HUNTING, TRANSPORT ETC. THAT GUY MAY BE BETTER SERVED BY A BIT MORE TENSION AS A BASELINE, SAY GOING 5-6 BELOW A LOADED ROUND DIAMETER, THEN COME BACK UP 1-2 WITH A MANDRAL
I wonder how much of the interference fit is lost after you shove a bullet down in it. The bullet basically acts like an expander mandrel opening the neck there has to be a point of diminishing return where all we're doing is overworking the brass. 🤷🏼
You got through that entire video with using the term “Fudd lore.” Well done. After all, long held “truth” being parroted by people that haven’t tested or thought critically about it is Fudd Lore.
I have always thought it was weird how neck tension was expressed since brass has springback. Just giving it some thought, having not tested, perhaps the way the average person can achieve the best consistency, given everything else is done the same way to the brass, is to use the bullet as an expander so the brass yields. If the brass was prepared right and consistent in theory this would yield a consistent holding force. But other issues may arise, controlling run out (a seater die could be made to control this but would probably have to be custom to brass due to neck thickness variance) damage to bullets, crushing cases. Just some quick thoughts -edit- I forgot to put that measuring seating force with something like the amp would be ideal.
