EBR accuracy help

[theduc]

I know I'm relatively new(long time lurker) but I am in need of some help.

I have a SA made M1A scout in a sage chassis(mod 1), which i love but it is starting to frustrate me. Went to the range today to figure out what load she favors(recently received my optic, sn3 1.8-10x44). Tried corbon loaded with 155 scenars, 170gr lapua lockbases and three 175gr SMK loads(black hills moly, SSA, and FGMM). My issue is of all of the match ammo shot, the rifle would not really hold a group(the FGMM and 170 lapuas did ALRIGHT). It was more like patterning a shotgun. When i first mounted the optic i zeroed with DAG surplus because it was all i had available, then re-zeroed today with the FGMM. I know that would spawn a problem with POA/POI but i was just trying to see which round would hold the tightest group with my rifle. At the end of the day none of the match ammo did any better than the DAG. at first i thought it was shooter related(ie i suck) but i am able to shoot much more consistently than the rifle was. Could this be barrel related?

Sorry for the long winded post, I just wanted to give as much information as possible. oh forgot, i was shooting for groups at my zero distance(100yds). The tightest 5 shot group the rifle would hold was about 3 or 4 inches, maybe a little larger.

 

[shawn_c992001]

Re: EBR accuracy help

I'd say something may not be tight. Check all your connections.

 

[wrecklessfool]

Re: EBR accuracy help

Check your gas cylinder for play. A lot of accuracy issues with the M1A can either be traced to the stock or the gas system. I think your stock is more than adequate given the bedding block.

 

[kraigWY]

Re: EBR accuracy help

Here's a trick that might help:

Take the action out of the stock. You will notice where the metal contacts the stock you will have dark rub spots.

You will notice this on the sides of the mag well and and the horseshoe section at the back of the action. Also, the lips where the trigger guard snaps in.

OK now find some of the yellow folder paper. Cut strips to match the dark spots on the stock, dont for get the lips for the trigger guard.

Try two layers first. While you have the action out of the barrel, put some good grease where the lip of the gas system matches the metal on the front of the stock.

Now carefully, without disturbing your folder stock, put the action back in the stock. You're really gonna have to ramp on the trigger guard to get it to close.

What you have,in reality done, is a temp. bedding job. Not take the puppy out and give it a try. It should hold up for a couple hundred rounds.

If this works,then you should find someone who has done accurizing jobs on M1As and get them to bed it for you.

I use to do this when I was shooting for the guard for people who'd show up at a match with a service grade M1A, you'd be supprised how much it helps.

Short of that I wouldnt venture to guess without going over it with a set of gages.

 

[wrecklessfool]

Re: EBR accuracy help

The OP has his M1A riding in a SAGE EBR which uses a proprietary op rod guide block for installation. The rifle is essentially bedded using 3 hex head bolts which attach through the stock to the op rod guide block. One of the advantages of this EBR chassis are that the rifle needs not be bedded for good results.

 

[Alpha_Tango]

Re: EBR accuracy help

Duc - I have been working through the same issues with my MK14 build. I dropped a SA Scout Squad barreled action into a Sage NSG Mod 0 stock (barrel is an 18" heavy SS SA custom shop) and mounted a Leupy 3.5x10 M3 on it, expecting decent accuracy results. Wasn't cycling right when I first got it from the seller and it was shooting 3-4" groups... so, I had the entire USGI gas system replaced with an SEI system and had the bolt/head spacing checked by my 'smith (who's been working on M1As for 25 years and I'm confident he knows what he's doing). I got it back last week and its now cycling properly/consistently, but its is still shooting 3-4" groups @100. Incidentally, while I was waiting for the scout action to return from the smith, I ordered an extra op-rod block and dropped my stock SA NM into the Sage - results were sub MOA to 1.5 MOA groups with that set up (shooting basically as it did in its primary set up - a bedded McM M1A stock).

Based this experience and on what I've been able to glean on the interweb + discussions with long time service match/M1A guys, I am coming to the conclusion that it is the scout set up (which was designed/modded for CQC/B and portability - think tanker or paratrooper rigs) that is the root cause of inaccuracy issues here... others may differ on this, but my recent experience is causing me to re-think a Sage Mod 1 + LRB M14/scout build I was planning.

Perhaps H20Man will chime in here to help/correct the M14 unwashed (me)?

Good luck with remedying the issues on your end. For the record, I am keeping my Mod 0, but will be dropping an Aimpoint or Trijicon red dot on there for use in CQC/B zombie scenarios. Will move the M3 onto a shooter.

 

[theduc]

Re: EBR accuracy help

Thank you for all the help thus far. Gas system was tight. The rifle cycles/operates flawless, just with piss poor accuracy. From reading on the internet, it appears the way to achieve accuracy with m1a's is to throw money and quality smith work at it. Which I am trying to avoid for the immediate future. I am however considering sending the rifle to warbird and having it rebarreled with a medium weight match barrel and maybe having the trigger smoothed out a bit.