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judgedelta said:
I bookmarked and will read it carefully. Anyone got a favorite, (reliable, accurate, safe) pet load for a M1A?
Lake City 67 Match case
WW large rifle primer
168 gr Sierra or Hornady Match bullet
41 gr IMR 4895

Fired thousands of them in a Winchester Model 70 Target rifle and a Springfield M1A. They did well in both rifles. Never segregated any loads, just used them in either rifle.

Doug
 

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If you look in the Hornady reloading manual it has loading data just for a service rifle, because of pressure concerns so be careful if you are going to load for a service rifle.
 

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Tub Horn said:
If you look in the Hornady reloading manual it has loading data just for a service rifle, because of pressure concerns so be careful if you are going to load for a service rifle.
Hornandy's max loads are way below what actual service rifle shooters are using.

If in doubt go by the book, but those loads are not on the firing line at Perry.
 

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judgedelta said:
Doug:
What about the same load in commercial cases? Would you go up a grain or leave it as is? What overall length? Thanks...
All you can do is try it. At least it would not increase pressure. I use a chronograph on most rifle loads.

Doug
 

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I discovered another serious issue not presented in hardly any of the essays about loading for service rifle.

I use a mild load, all the bullet has to do is punch a hole in paper after all, and I've been using the RCBS X-Die which eliminates the need to trim cases, vastly extending case life.

The problem is, and it wasn't only with X-die sized brass is my primers just weren't seating deep enough. I figured my Lee hand primer had worn out but when I got the Dillon, the same thing occurred so I researched the issue. It turns out the primer pocket thickens! Every firing makes it shallower than it was before! The cure is a primer pocket uniformer sold by Sinclair or Lyman. I picked up one from Bass Pro Shops, it's basically an end mill with a stop collar to machine the pocket to uniform depth. I'd always known they were used by the benchrest crowd to get everything exactly the same, but hadn't realized service rifle loaders need them too. After uniforming, primers are .004" below flush.

I took mine out of the handle and chucked it in a drill and found out my pockets were so thick the tool's teeth would fill with brass and it wouldn't cut deep enough. I pull it out a time or two, clearing the chips out and it seats against the collar like it's supposed to.
 

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As I said, I loaded thousands of these loads for my M1a. I shot the original NM barrel off the rifle, then rebarreled with an Olympia Arms NM barrel and did a reglassing of the rifle. The load was great in the M1A and in my Model 70 Target Rifle it would shoot 3/4" groups at 100 yards from the prone position. I once fired a 200-13X on the 100 yard MR-31 target, with the Model 70 Winchester. The overall length I used was the same as the Lake City M118 7.62 NM ammo.

Doug.
 

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Dusty Rhoads said:
PhilipM--regarding the primer pocket losing depth: is that with Lake City brass?
All cases do this as far as I know. Here's a LC 69 I cut and has an offset flash hole, something I see only on LC cases.

 

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The reason I opened my mouth wuz, the 7.62X51LC I useta shoot is way harder and beefier, at the expense of case volume, in the case head than the WW .308 I use now. The Federal brass that I used for a little while quickly started to loosen up on the primers, and I wasn't loading hot (168s, 41.5gr. 4895).
I thought about culling cases with offcenter flashholes--some people do--and decided against it 'cause there was so many. 'Course I didn't hit much of anything, either.
 

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Good info Phillip. I shot today with my M1A and had doubles twice. That did not surprise me as I had measured the new Winchester commercial brass and most had shallow pockets. I got in the Sinclair tool and before vs after using the tool there is a big difference. With a calibrated depth micrometer some of the loads were between .0025 and .003" on the primer below the base of the case. I'll feel better with that depth being about .004 to .006". BTW, one of the doubles I had loaded the CCI #34 primer, but it just would not seat any deeper than .0025". There is some difference in primer heights between different brands. Tim
 
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