my m14s shim job... what a difference

4

45ACPKING

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this is to all of you who have bought a norc m305 or m14s and have not yet tinkered with some of the fine tuning......it's easy as pie, give it a go. Given, one must have a few dedicated tools, i got me a gas cylinder wrench off ebay, and made my own, very handy dandy, castlenut pliers and grabbed a couple gas system shim kits from mysticplayer gere on CGN. With the bolt locked open, I had some definite play in my gas system and a rather loose stockband. I printed off Skullboy's instructions from the stickies at the top of the forum and followed the instructions to the letter. The flash hider was a bit of a trick because the soldering dots underneath the rear band were tough to spot. I drilled then out with a end mill type dremel bit to about 1/16 deep. I loosened my castlenut as far as it would go and, setting a wood block behind the sight area, gave a sharp wrap with a hammer, freeing the flash hider from the solder. My homemade castlenut pliers did the rest and off she came. Next my gas system lock ring was loose as soon as i removed the gas nut. I would say it would be tool tight at 1 o'clock!!, past the 6o'clock specified :eek: I believe the shim kits were 4 per set and it's a good thing i ordered two sets, it took 7 shims to bring it to where i felt it was just right.

While I had her all apart I disassemble the whole rifle, down to receiver and barrel, again, following the instructions of the likes of skullboy and hungry (and others ;) ). I swapped out my bolt which was sticky and tight to begin with for a new in the box TRW usgi bolt, which did drop right in :) , I reassembled the rifle, no play whatsoever in the gas system and the front band does not budge, she's rock solid. The bolt was smooth as a babies...... hehe now i just need a rooster spring guide and tac bolt release. I'll prolly get her to the range monday and I'll post a report.

I just wanna thank all the guys on this site who are posting the info on how the average guy can tune up this rifle, your postings and ideas are invaluable and MUCH appreciated :) :)
 
45ACPKING said:
I swapped out my bolt which was sticky and tight to begin with for a new in the box TRW usgi bolt, which did drop right in :) , I reassembled the rifle, no play whatsoever in the gas system and the front band does not budge, she's rock solid. The bolt was smooth as a babies......
Click to expand...

CAUTION, even though the bolt dropped right in, you still need to have the headspace checked with a proper set of headspace guages.

Fitting/lapping of the bolt may still be required for a proper & safe fit.

DO NOT SHOOT THIS RIFLE UNTIL THE HEADSPACE HAS BEEN CHECKED!!!!!!:eek:

When I installed a TRW bolt in my Shorty M14, it dropped in and fit perfect, but the bolt would not fully close & lock up on the shortest guage (1.630" - SAAMI minimum for .308Win).

It took roughly 45 minutes of lapping to get the bolt propperly fitted so the lugs completely locked up without any binding or sticking.It ended up headspacing at 1.630".The minimum for a .308 Win. Chamber.Nice and TIGHT!!!(just like prom night!!!!!:D ;) :p ).

I have a complete set of headspace guages and the bolt lapping tools if you need a hand.

SKBY.
 
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hehehe i'm gonna do a headspace check on sunday, my bro has the proper tool. i've got the lapping compound as well. I appreciate your warnings though... will proceed with caution :D :D
 
45ACPKING said:
hehehe i'm gonna do a headspace check on sunday, my bro has the proper tool. i've got the lapping compound as well. I appreciate your warnings though... will proceed with caution :D :D
Click to expand...

I have bolt lapping instructions in the M14 FAQ Post as well if you need guidance.;)

Just remember that the bolt is stripped, and use a sized case in the chamber as a cebtering guide or else the lugs will not be lapped evenly.



SKBY.
 
i printed off the whole thread from stock filling to bolt lapping and lubing instructions.... all 13 pages LOL..... hey guys.... Skullboy has become my guru hehehe :D
 
Remember to send me 5 fired cases for confirming the size of your new chamber. All you need is a cheap and smallest padded envelope. 2 stamps will get the cases to me. I'll email or PM your chamber dimensions BACK to you and then you will have an idea of how large your chamber / fired brass is.

Just to give you an idea of why and how this is important to know....

After paying $ 699 for an M305 from Milarm back in 2002, I fired the rifle and measured the chamber with M305 factory bolt: 17 thou ... This is large but 8 thou smaller than the NATO NO-GO gauge of 25 thou. So the 17 thou was acceptable, but not for a reloading competitor like myself.

I dropped in a new TRW USGI bolt and I did not have to do any lapping. Holy Shzt ! It was made for this rifle... I was damn lucky. When I fired the rifle with TRW bolt, I miked the brass and it was DEAD Nuts on 0 thou or 1.630" SAAMI spec.

I immediately PM'ed Skullboy and said, "How do you like me so far?"

"You wanna get summa this ?"

No seriously, I had to share my findings with him and lure him to the M14 addiction further and further. The rest is history.

45acpking: I'm happy as heck that the M14 clinic material and the stickies posted above are handy. We are not trying to make gunsmiths out of you. We are merely "empowering" you M14 owners to the joys of tweaking your own M305's and truly having the fun that was showed to me 20 years ago by my "retired" NRA High Power coach. We are his legacy , I guess.

Cheers,
Barney
 
And his legacy and your legacy continues! From all of us M14/M14S/M305 owners, thank you very much.

I replaced my barrel and gas system up at Hungry's M14 clinic in Collingwood and didn't need to shim, it was tight enough. Everything worked out perfectly. I still get a real big smile going when I watch the older clinic videos.
 
Mine started off as a 4-5moa rifle. I shimmed and indexed mine at the clinic too. Several thousand rounds later, it still shoots sub 2moa. Almost boring now. Guess I'd better build another...Mark
 
I haven't swapped bolts yet (still can't afford a good one), but I did shim my gas system. I unitized my gas sys too. I have to say that my groups shrunk. Maybe I didn't need to have the welding done, but it's hard to say which made my groups shrink, as I did both mods at once.
 
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