Is it safe to shoot .310 bullet in 308WIN?

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HankC

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I have plenty Nosler 7.62x39 (.310 Diameter) 123 Grain FB tipped (jacket) bullets that would last more than a life time, bought when it was cheap. I load and shoot them in my 308 bore 7.62x39 bolt gun and AR but I wonder if it would be OK to load them in 308WIN and shoot in my 308 bolt guns? 308 bore 7.62x39 likely have deeper throat and lead in than 308WIN, OK in 7.62x39 with 308 bore may not be OK in 308WIN, but .002" is really nothing. Any experience?
 
I have shot 123 Gr Z-Max .310 bullets in 300 Blackout with no issues. I did a cast of the neck area to be sure I had plenty of clearance. I would assume you should stop short of max charges because of it. My Blackout shot them well.
 

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I was actually thinking loading them in 300BLK while 300BLK has deeper throat to accommodate subsonic heavy/longer bullets, but 300BLK also has tighter neck that thicker brass many not chamber at all, so I wondered if loading with 310 bullets would chamber. If works for you, I will try. I don't load to max load, may reduce a bit if load them in 308WIN.
 
It has been done, and I have done it. I would, and did, back the loads down a full 10% from max. I was shooting some Comblock pulled API from 7.62x54R from a 7.62 NATO G3 variant at the time with VN140 and whatever RUAG 7.62 NATO ball was loaded with. Maximum velocity was not a concern so long as they cycled the action reliably and could hit a relatively large target to 500m. We had an ample supply of NATO ball, but had the need to set vehicles and cinder block wall buildings on fire and didn't have any API, so we found/made our own.
 
There's plenty of room in the neck & ball throat of a standard 308w chamber

A standard 30-06 is .340" in the neck
A standard 308w is .344" in the neck

Ball throats are typically .310"

What that .310" bullet will do is raise the short start pressures burn the throat of the bbl out faster.
 
I shot plenty of .311 and .310 bullets through my 30-30. But they were reduced loads.
 
Is it safe to shoot .310 bullet in 308WIN?
The question is for a 123 gr, but I've wondered about 150 ish grain bullets as well.
 
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I have used my RCBS press and a Lee push through .308 sizer to size .311 jacketed bullets down. Just use good lube. Then you know they will work. I noticed no accuracy issues either. YMMV
 
In a bolt action rifle, 0.310 bullets would be safe to shoot with the starting powder charge, and yes 0.002" can make a difference in chamber pressures. I had a safe 308 Win load for Hornady 165 grain bullets. I changed brand of bullets because the price was right on 500 count boxes of bullets. New bullet was .308" diameter but bearing length was much longer. First 3 rounds had very high pressure and flattened primers. The new safe load was 2.3 grains less powder with similar accuracy.
 
Ackley experimented with very substantially oversize bullets. His conclusion was that since it does not take a lot of force to engrave (or extrude) a bullet, an oversize bullet makes little difference in peak pressure.
 
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