M305 is it rated for commercial .308 ammo?

steyrm9a1

steyrm9a1

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Hi all, just a question, i have a m305 that ive been shooting commerical .308 thru. My owners manual said its .308 winchester. Is it .308? or is it 7.62 x 51?
I know there are slight differences in max CUP pressures. I want to start reloading and im wondering if i should be loading for 7.62 x 51 pressures or commercial .308
thanks.. i just want to keep it within safe limits
Dave
 
If your manuel says 308win than its 308win.
Unless you are useing the max loads for 308 I wouldn't worry too much.
Generally you start with the minimum load and slowly work up .2grn at a time without exceeding the max load until you get a good grouping, then that is your load and doubtfull its a max load.
 
Keep the bullet weight ranging from 168 and 150 gr with factory loads. The problem is that semi autos in this platform require a steady slower burn rate for this kind of unregulated gas system. You'll slam your operating rod hard and the Chinese bolts and parts don't hold out well with higher pressures. Its easy to find 150 gr factory ammo, but still seems to be on the hot side with the big manufacturers catering to the bolt gun crew. I reload with 4895 or Varget with 150/168 gr on the tame side with my M1as and Garands. You could also get an adjustable gas plug for a wider range of ammo. I don't bother.
 
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Older remington ammo used to give slam fires. I haven't had/seen any lately with any factory or properly constructed ammo. Fouled bolt assemblys can produce slam fires as well. Then again any free floating firing pin bolt assembly can produce this.
 
I found my M305 mangled up soft point .308. When I went hunting, loading and unloading the same round - the tips of some of my rounds were really banged up. Still bagged my first deer with it - but it was quite irritating.
 
it is really made for the 7.62x51 ball ammo. But .308 works ok if keeped at 150 gr for bullet size I always used cci military primers with mine since i had some slamfire issues with the remington target stuff
 
Max pressure of 7.62 and 308 are about the same. 308 is available with heavy bullets that use slow powders that boost the port pressures too high.

Use 7.62 or 150 gr commercial, or handload with medium power loads with 150 to 168 gr bullets.
 
Ganderite said:
Max pressure of 7.62 and 308 are about the same. 308 is available with heavy bullets that use slow powders that boost the port pressures too high.

Use 7.62 or 150 gr commercial, or handload with medium power loads with 150 to 168 gr bullets.
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jamiejaf said:
Keep the bullet weight ranging from 168 and 150 gr with factory loads. The problem is that semi autos in this platform require a steady slower burn rate for this kind of unregulated gas system. You'll slam your operating rod hard and the Chinese bolts and parts don't hold out well with higher pressures. Its easy to find 150 gr factory ammo, but still seems to be on the hot side with the big manufacturers catering to the bolt gun crew. I reload with 4895 or Varget with 150/168 gr on the tame side with my M1as and Garands. You could also get an adjustable gas plug for a wider range of ammo. I don't bother.
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Okay now I'm confused, one guy says slow powder and heavy bullets (I'm gonna guess he means 180gr or something) of the commercial stuff will damage the rifle.

The other guy says it needs slower powder to run (with the lighter bullets, 150-168gr).

So essentially the heavier bullet it has to push, the higher pressure the rifle is subjected to? If two separate loads are the same, have the same slower powder. But the bullet weights are different the heavier one will be harder on the rifle.

So for the m305 a guy wants: reloading wise
150gr-168gr bullet
Slow burning powder (any suggestions? I have mostly IMR 4064)
Tough primer

Correct?

Any factory .308 stuff out there that accurate in the rifle and won't be hard on it? (Not including the noriinco 7.62 stuff)
 
Good information on M14/M1A reloading can be found here:
http://www.zediker.com/downloads/14_loading.pdf

You do NOT want overly slow powder for M14-type rifles, as high port pressures will be hard on the action. Your IMR 4064 is the slowest-burning powder that is suitable. Other good choices include:

-W748
-H335
-BL-C(2)
-WC 735 surplus from Higginson's (use data for either H322 or Accurate Arms Data Powder 2200 as a guideline for charge weights)
-4895 (IMR or Hodgdon)

The biggest thing you have to be aware of for reloading is headspace. Most of these rifles tend to have a lot of headspace by commercial .308 standards, with correspondingly short case life. Be sure to inspect your brass for incipient head separations. In extreme cases (headspace greater than .010" over SAAMI "GO"), neck sizing may be required to minimize working of the brass.

Basically, any commercial 150-168 grain factory .308 will be safe to use. The belief that there is a major pressure difference between .308 and 7.62 NATO is due to confusion between copper crusher (often given as CUP, but sometimes psi) and transducer (always given as psi) pressure measurements.
 
BL-C(2) is one of the best powders I've tried with my rifle, 45.3 Grains under a 150 Grain Hornady SPBT with a CCI 200 primer. Might be a little on the light side, but it does everything I want it to do.
 
I solved this issue in my rifle a long time ago. What I did was research the ammunition the rifle was designed to fire - and basically stay within those parameters. Back in the day, the ammunition was rated as 2,700 fps to 2,750 fps with ball powder. The closest bullet to spec is the 150 grain - flat base, so that's what I use. I use Win 748 exclusively. I load to 2,700 fps and use CCI magnum primers. (with 748 - I exclusively use magnum primers - even for the little 223 - I do not load them to the max either). The slam fire issue is non-existent as I have not had one ever with the commercial or my loaded ammo. The rifle has also not ever had a stovepipe or problems with the reloading process resulting from the ammo either. The oprod spring/wheel bearing grease in winter - yes, ammo no.

I full length resize my cases. If your headspace is a little out (which is NORMAL), what I did was back out the case resizer to .005" (based on measurements from my rifle) to bring it back within SAMMI spec. The biggest problem is that the extractor tends to chew on the rim, so I typically reload the casings 5 times - although, I have had some with way more reloadings. The important thing, as small as it sounds for consitency is to make sure your casings are trimmed for consistency, as I do crimp the bullets into the cannelure. With mine I added the .005" to my trim spec. I changed out my bolt a year ago or so and now the headspace is well within the commercial SAMMI spec - so I use the Lee hand trimmer with a drill assembly. Very fast and efficient.

The result, is that my rifle is pleasingly accurate, reliable and very fun to shoot.
 
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harbl_the_cat said:
I found my M305 mangled up soft point .308. When I went hunting, loading and unloading the same round - the tips of some of my rounds were really banged up. Still bagged my first deer with it - but it was quite irritating.
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The solution for that is to use one of the plastic tipped bullets, they stand up to multiple loading/unloading cycles much better than anything with exposed lead at the tip.


Mark
 
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