The problem with mean radius is that since almost no one uses it, or reports their results that way, it is impossible to make apples to apples comparisons.
@@boydallen8059 There are ways to convert from mean radius to expected average group size for a specified number of shots and vice versa. There's a book called "Statistical Measure of Accuracy for Riflemen and Missile Engineers" that has conversion factors. You can find updated conversion factors that are more precise online. Anyway, that book goes into why extreme spread is one of the least efficient measures of precision imaginable (mainly because it throws out all the information about all the shots in the group except for 2). That said, yes, the main problem with mean radius is that pretty much everyone uses extreme spread which is really inefficient and highly variable in comparison.
@@michaelhill6451 I am familiar with mean radius. My point is if the goal is to communicate, and discuss it is probably better to stick to common standards rather than to tell them to read a book as a prerequisite.
Excellent video presentation, step by step showing "problem" areas, corrective actions and final evaluation. The barrel faults seem to be the base problem after your process. Lots of time/work but we'll done! Thank you!
Some of my most accurate rifles, tikka's M55's had the most slop in the bolts, what fixed it them was free floating bedding action recoil lug & trigger job, proper toque setting on scope mounts action screws.
Picked up a used Thunder Ranch MVP in .308 for cheap. The man said the rifle shot all over the place, so I disassembled it, cleaned it, and discovered the action screws were the wrong size for the action. I fixed that with aftermarket screws and some Loctite. The gun dislikes premium ammunition; the lower quality the ammo, the better it shoots.
Good stuff. As others have stated already I too would have liked to see the barrel recrowned. Additionally that barrel is in serious need of a deep cleaning back to bare metal. Remove all carbon and copper fouling then work it with JB Bore Compound until it squeaks. One final thought, go ahead and replace the 2-piece scope mount for a solid one piece and bed it to the action. After those simple steps it may very well shoot sub moa with decent factory ammo (though handloads would be preferred). Thanks again for the good video.
I work on one of these exact copy and caliber. It shot the least expensive ammo from wal-Mart. Bulls eye. I don’t remember the brand. We tried premium ammo several reloads. It shot great with the least expensive ammo.
Agreeing with some of the other comments, I think some changes in factory ammo choices or some tinkering with hand loads would easily produce sub-MOA groups
I just torqued everything and lapped scope rings and torqued scope mounting. Worked out a 77 grain hornaday factory ammo. 2" group @ 200 yds. Would not group with cheap 55 grain ammo.
I might have missed it, but I didn't see you address the muzzle crown. For me your muzzle had a clear problem in the bore scope video. Timeline would be around 12min 11 sec. I would clearly do a recrown. Personally I do the brass screw technique and am finished in a about 15 min altogether with a coarse and fine grinding compound.
I seen that too, I'm thinking well you got to smooth out the crown........ Another thing was all the chatter marks father down the barrel, looked like hell itself. I wouldn't want this rifle for a varmint rig with that rough barrel.
@@armedfarm3429 The chatter marks wouldn't worry me one second. Maybe 50, maybe a hundred or maybe two hundred rounds need to be put downrange until the barrel is worn in. But in the vid the work that could have been done is only finished to 50% in my eyes. Before the crown hasn't been addressed there is no way a summary can be drawn.
@@7sleeper7schlaefer72 Wouldn't bug you, but it'd bug me. Thats why I said I wouldn't want it for pickin varmints. Coyotes be ok, but no prairie dog towns with this low-quality barrel. If Mossberg don't start making some decent barrels they might as well quit making rifles. How you can say the barrel won't be a problem after a few hundred rounds pass, you are dreaming. Throw the barrel in the dump & get a real one. Didn't you see the inside? Take a look into a decent barrel!😣😲
They do shoot sub moa. My first rifle I started handloading for was MVP LR in 308. It was a great cheap beginner rig. I have a video proof of its sub moa performance.
What caused the uneven wearing of the lans (sp) was the barrel and the action mis-aliened at the factory ? Sounds like it ? So a new barrel will under go the same problem if that is not corrected as well ?? Is so I would guess both a new barrel and action ?? Seems that this rifle isn’t worth fixing ??? That is the best data ! Do I dump more money at this rifle or sell it as a parts gun ( Stock, trigger, Bolt and such )????
I was told by a friend they had called mossberg to ask about a replacement because his rifle wouldn't shoot 1MOA and he was told mossberg doesn't have a sub moa guarantee.
did you bed underneath the plastic piece in the stock? try putting the indicator on the forend of the stock and see how much movement you get. I've bedded three of these and see big improvements. I have some data from one of my F-class rifles to support that the lands being uneven isn't that critical. it was throated with a PTG unithroater, and it looked worse than that mosberg. it shot amazing. I won a few matches with it and obtained highmaster classification with it. the muzzle being bigger could be an issue, but how much is it actually affecting it. I mean, we really don't know. before you come to a definite conclusion, I would double-check your bedding if you didn't bed under that plastic piece. that factory ammo may just never shoot better in that gun. may have to reload to really see how much you improved it.
I agree that I think the bore diameter issues are more critical than the chamber alignment, especially in this video because it's not super drastic compared to some I've seen
Also try some 77grains and 62grains bullets on my Savage 12 bvss 223 the 77grains bullets work's great even though it has a 1-9 twist rate, 55grains bullets usually stabilize at 200mts on by rifle but at 100mts they group poorly. Great video I hope that you can continue on that project.
It seems like rifles tend to be the accuracy of the lowest accuracy component. So things like bedding and lapping only make a difference if the barrel and ammo is near perfect. I wouldn’t mind putting a premium barrel on a cheap bolt action but on these mossbergs they seem to have some plastic in places that makes be go “huuh?”.
@13:23 Bore at muzzle feel looser than bore at throat made me close my eye in hopelessness. Barrel is trash. Also that throat and bolt 30-10% lug engage LMAO
If its like the 3 mossberg rifles my nephew went threw which is a day long story in its self 10 different types of ammo and 3 inch group out of one of the rifles was best we every got the other 2 was at best 5 inches he traded it off finally and got a cheap savage that shoots .75 groups all day long
I have one in 6.5cm shoots Hornady eld x 143gr. .77-.88 stock out of the box with only the trigger lightened to 2.5 lbs. A 308 stock except for the trigger lightened to 2.5 lbs that shoots federal fusion 1 inch to.75. I'm ok with that! However I have one in 300win mag that shoots 3 moa no matter what ammo I use. Factory or reloads. It's going away soon. I have several Mossberg patriots, I'm happy with all of them except the 300 win.
No. I had to remove it to do the work, but I used the same optic. I even left the turrets in the same place to see if there was a noticable/dramatic shift.
@@reeseontherange I guess what I'm saying is, if it is the same scope, and not a different and proven scope, could the problem be the original scope itself ?
@@douglaskurka5874 I hear what you're saying. I've used this same scope and mount setup on my match rifle and it worked really well. That gives me confidence to say that I don't think it's the scope. But crazier things have happened.
Had one of those in 308 after 4 brands of ammo and best group of over 3" it went away after 2 weeks got a savage axis 2 in 7mm08 American whitetail ammo under 1" all day long.
@RG_outdoors285 you can understand how skeptical one would be over claims that a 1moa rifle plus inconsistent budget ammunition = less than an moa all day
@RG_outdoors285 they're loaded on the same equipment, and I can see the outfitter line being less accurate with the finicky bullets they use, but not being able to produce more consistent ammunition than factory? No offense, but that's pretty bad.
Have a synthetic stock version in 6.5 Creedmoor and wont group under 2 1/2 inches with 10 different loads . Factory by the way but i have one more to try . Crossing my fingers
Does Mossberg list their accuracy under the same as the Mossberg 500 with birdshot? All joking aside good work, but that barrel towards the south end, including the crown screams problem for me. New barrel or make a short barrel and rechamber. If i had the tools on hand the latter would be it if I was keeping that rifle.
^This. I recently bought my first Tikka (A CTR Stainless in 6.5 Creedmoor) and color me impressed. It shot < 0.5 MOA on average for 5-shot groups out of the box with the first random handload I tried in it. That wasn't a fluke either. Basically every bullet I've tried in it averages right around 0.5 MOA in terms of extreme spread for 5-shot groups or 0.2 MOA for mean radius. I got a KRG Bravo chassis for it about a week ago. I can't wait to see if it improves things, which would be difficult since it already shoots so well. In the worst case, it looks cooler. Lol.
Personally if I have to do that much work to get a gun shooting I’m better off spending more money for a higher quality rifle than spending 400 bucks for a cheap mossberg or savage. I have always ran either a Ruger or a Winchester rifle and I never had an issue with accuracy. My model 70 Winchester out of the box I’m getting sub moa accuracy with two different types of ammo from 2 different companies.
I bet UR wishes he never did that vid. Have not seen a gun toober sh*! The bed that hard in a while. That or it was a epic troll vid. It was done with backfire.So it is a solid possibility
Never heard of a mossberg that would shoot MOA, Buy a reputable gun maker rather than someone who is new to the game, Just shot a T/C Compass 6.5 CM for a friend that put 3 shots into 1/8" (no mods, factory ammo). If I could post pics I would. Mossberg has always had a sloppy reputation, You can find inexepensive rifles at the same price point that will shoot well in their factory form. What a POS. Long story short, don't buy these...
So many reports of the Mossberg rifles not shooting well. They look nice, but if you want a proven Mossberg, buy their model 500 shotgun.. At least it has an excuse for patterning like a shotgun. Because it is one.. Also, without even watching the video, I'd be suspect of the barrel first. All your other checks are crucial, but the barrel has more effect on precision than anything else. Also proper glass bedding of the action, and proper scope mounting is key. The big one is the barrel though..
If you want to shoot sub MOA you will have to learn how to shoot. less gun more you and ammo. good luck. None of this shit will help you get a better sub MOA.
Hello is there a way I can get in touch with you I was wondering if you can help me fix my dads firearm it’s a INTERARMS MODEL FIRESTAR, 45CAL SEMI AUTO PISTOL, S#2053837 he was in the marines and he passed away a couple years ago I’m really looking to get it fixed so I can get it mounted
