Shooting .308 out of M305

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MartyK2500

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I have this real nicely tuned M305

Still got chinese bolt in, got the rcbs precision mic, measured my fired cases at 1.642" headspace.
Which is between 7.62 no go and field if my memory is good

I know it's well over the .308 saami max
And know of risks of headspace separation.

Don't feel like dropping an extra 300-400$ for an USGI bolt, but would like to shoot a 150/155gr hunting round, which would put me in 308

Id reload once fired cases i have, and then lose them, as in not reload them a second time
An opinion, as i know books say otherwise, would you shoot 308 out of an M305 headspaced at 1.642?
 
That's a "GENEROUS" headspace for sure!! but, it should still shoot fine. I have one I just picked up from a fellow as a donor for the USGI parts that Wolverine was selling and apparently that's what his measured and apparently it was a good shooter. Keep and eye on your Brass for case failure and shoot away!!
 
Yeah gas was turned off
Also had forster 308 field and 7.62 field gauges in hand
Iirc, 308 field is exact same measurement as 7.62 no go
Closes on 308 field, does not close on 7.62 field

For my tactical long range bolter, i am really demanding with my brass as in all same manufactures and specs. Thats where i had the idea, all these once fired casings i dont want to reload for precision 308, i could buy a hunting projectile and use in M305
 
At 1.642 I would seriously consider swapping the bolt. (You are only 3 thou away from nut cancer! :D )

1.642 is my absolute max on customer rifles, any more than that and I start swapping bolts from the parts bin.

I personally think that 1.638 is a pretty good balance between NATO & 308. A fella can reliably feed the rifle any and all commercial 308 150 gr ammo as well and type of nato surplus ammo.

For match chambers, I cut the chamber at 1.631.

John
 
Thanks for replies
As is i don't think i'll feed it .308

I'll just safe queen it for now, until i have a plan
Bolt does bear on two lugs so i am not scared to cycle plenty 7.62 if ever i get back into that
 
I think i may have found a safe compromise.
What do you guys think of Hirtenberger 7.62x51?
Peeps at local range say it's too hot for M305, but i wouldn't see why.

I could plink with it, keep nato casings to reload a hunting round when needed.
 
Hot ammo would only affect the gas system and force of bolt slamming back right?
By having my S&J 10% extra strenght op rod spring guide spring, i would imagine it would protect the gas system a little bit more
 
It's the op-rod and the bolt roller that take the beating with hotter ammo.

I have found that while it is a touch warm, it is still with-in velocity specs for the NATO cartridge.

I have run a couple cases through a few different rifles, and it doesn't seem to be any hotter than the rifles can handle. I am running the S&J hardware recoil spring in all my rifles, I use them on all my builds and include a new spring in all my packages.

Definatly worth the cost of a box of shells!

John
 
Dimensionally 308 & 7.62x51 are pretty darn close. Once you fire it in your rifle it will be fire formed.

I would load the x51 brass with 308 dies, and use a 308 load reduced by one grain of powder. I recommend using Hornadys service rifle load data.

John
 
Here is something that I think is a good read for anyone planning on loading for the '14 platform.....

Shamelessly stolen from the firing line forms (M14 forum) the quote is from there.

voland said:
I did a fairly in depth read of the "Reloading for the match m14" by Glen Zediker and I wanted to summarize the details from the article without the explanations.

http://www.zediker.com/downloads/m14.html

I think that Zediker did an outstanding job explaining in detail why the m14 is special and its worth a read but I want to have a beginners guide if you will of do's. I am silly like this and I learn by retelling what was explained to me so this is really a learning experience. Please take a look and let me know if I missed any details or if anything should be tweaked.

Best to use:
Case: LC brass
Powder: One of the 4895s
Bullet: Sierra #2200. 168gr HPBT
Primer: CCI
*These are the recommendations that Zediker makes to duplicate the Lake City Match M852/M118

The reloading process and details:

1) Remove the spent primer
2) Clean primer pocket
3) Tumble/clean brass
4) Use full length case sizing die to re-size the case.
*A small base body die from Redding is good for this job as it does not touch the neck of the case in the resizing process but sets the shoulder
**The shoulder has to get set back on these cases to at least 0.002 under chamber head-space
5) trim case as necessary
6) check case with LE Wilson or Stoney Point cartridge headspace gauge
7) use deburring tool to clean up the neck
8) Prime the case.
* set the primer a little below the the case head. .004 or more under the plane of the case head is good. this prevents slam-fires.
9) Drop in powder.
* Zediker recommends 41.5gr of H4895 but you should always consult your manual
10) Seat the bullet
*an oal of 2.800 is recommended by Zediker
11) Put a light crimp.
* This is an optional step. Zediker recommends a few thousands of an ???

"More than I know anything else in life, stick 41.5gr
H4895 in an IMI case with a CCI BR2
primer and cap it with a #2200 to 2.800
inches oal. Done and done."
Glen D. Zediker

thank you all for your time!
V.
Click to expand...

John
 
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