Hand loading for AR's vs bolt actions??

[barefooter56]

I'm sorry that was supposed to read "difference" not "distance".

The only "difference" is that the Classic Hunter fits your magazine . lol !

 

[HNDLDR]

It seems like it goes away after it's been shot for a bit. I don't heat my barrels up so I don't think its heat related. I didn't break in the barrel. Everything so far is pointing to fouling and I think it's definately time to scrub it out thoroughly and break it in properly, then make an assessment.

 

[barefooter56]

It seems like it goes away after it's been shot for a bit. I don't heat my barrels up so I don't think its heat related. I didn't break in the barrel. Everything so far is pointing to fouling and I think it's definately time to scrub it out thoroughly and break it in properly, then make an assessment.

HNDLDR,
How does it "go away"? What happens to the group? What direction(s) does it go?

 

[HNDLDR]

The groups don't seem to move they just get bigger. The gun hasn't been cleaned in a while and even though my other guns are still shooting great without being cleaned, I'm afraid this one is more temperamental.

 

[Greyfox]

Use the same loads in my R25/7mm. It shoots/feeds well with 140SST's and BT's, It holds .5 MOA accuracy for at least 200 rounds before cleaning. I did go through a barrel break in with it and found that it cleaned and improved in accuracy after I put about 100 rounds through it after break in. I also recommend placing a 1/8" thick rubber pad under the rear reveiver pin lug to make sure the reviever is tightly mated to the upper with no play. This is necessary with most AR platforms.

 

[HNDLDR]

I'm in the middle of cleaning it as I type this. It's taking much longer to get clean patches then normal.
The upper to lower fit is very tight on this one. My Bushmaster wasn't near this tight. Is that something that loosens up with time?

 

[Greyfox]

I'm in the middle of cleaning it as I type this. It's taking much longer to get clean patches then normal.
The upper to lower fit is very tight on this one. My Bushmaster wasn't near this tight. Is that something that loosens up with time?

Only one of my AR's was tight enough to where there was no movement when pressure was applied. After several years, it's still tight, but only with the original upper. I think if you keep the pins lubed and you are careful to not stress the assembly when hinged on the front pin it will stay tight. Generally, the Milspec tolerances are designed to allow for interchangeability of uppers/lowers. Brownells sells sells rubber spacers for a few bucks designed to fit under the rear receiver pin of an AR15. (Note:these do not fit the R25/AR10 unless the rear tab is cut off). Even they compress with use. I modify them by drilling a 1/8" hole in the center of the base and insert a small length of a Smith and Wesson rebound spring for reinforcement. With this modification they last for years with repeated use. There are also special cam/pins designed to take up the space but I have found that they can loosen up with shooting, and if overtightened, can deform the pin holes.

 

[barefooter56]

The groups don't seem to move they just get bigger. The gun hasn't been cleaned in a while and even though my other guns are still shooting great without being cleaned, I'm afraid this one is more temperamental.

HNDLDR,
Have you checked for a "loose" barrel nut ? Does the rifle have a free float hand guard on it? It MAY be fouling. But I do believe you will find its some kind of a mechanical issue caused by heat. Go to AR15.COM to see if you can find an issue like yours and see what the fix was or what may be happening.

 

[HNDLDR]

I have to work to get the rear pin in so far.. I suspect that the camo coating is what's making the tolerances tight. I guess I'll keep shooting it as is for now and see if it loosens up.

 

[HNDLDR]

HNDLDR,
Have you checked for a "loose" barrel nut ? Does the rifle have a free float hand guard on it? It MAY be fouling. But I do believe you will find its some kind of a mechanical issue caused by heat. Go to AR15.COM to see if you can find an issue like yours and see what the fix was or what may be happening.

I'm not sure how to check for a loose barrel nut? The hand guard is free floated.

 

[barefooter56]

I'm not sure how to check for a loose barrel nut? The hand guard is free floated.

HNDLDR,
Unless you have "tools" this is going to be impossible to do. Suggest you contact Brownells gun tech line for help finding a good AR smith to help you with this. 800-717-8211. They may also have an idea why your rifle is doing this.