7.62x39 Bullet Seating

buddyb

I bought a Ruger compact in 7.62x39.On this rainy Sunday afternoon I was loading a few different loads to see if the rifle had a preference.I had read about a load using Sierra 125 grain flat point hollow points designed for use in 30-30 loads,and I have most of a box of them.I am using 30 grains of Ball2 powder and it completely fills the case.When loading the Hornady and Remington bullets the cannular allows for pretty shallow bullet seating but with the Sierra bullets the cannular is further up from the base so it needs to be seated about twice as far in the case as the other bullets.I am concerned that seating that bullet on a compressed load will run pressures off the chart.I am an old man and have been loading my own for many years so usually when better judgement says stop and think this through,I do.   Any experience or advice? 

Horse Plains Drifter

Generally I think, a compressed load is not a big deal. I have loaded many loads(45-70 comes to mind)that were compressed, and that was a non issue. You could always back your load off 4-5 grains, and work back up towards the 30 grains. Keep in mind, that the bullet for the 30-30 is .308" in diameter. and I think 7.62X39 uses a bullet that is .311" in diameter. This may or may not effect accuracy.

nononsense

buddyb said:

I bought a Ruger compact in 7.62x39.On this rainy Sunday afternoon I was loading a few different loads to see if the rifle had a preference.I had read about a load using Sierra 125 grain flat point hollow points designed for use in 30-30 loads,and I have most of a box of them.I am using 30 grains of Ball2 powder and it completely fills the case.When loading the Hornady and Remington bullets the cannular allows for pretty shallow bullet seating but with the Sierra bullets the cannular is further up from the base so it needs to be seated about twice as far in the case as the other bullets.I am concerned that seating that bullet on a compressed load will run pressures off the chart.I am an old man and have been loading my own for many years so usually when better judgement says stop and think this through,I do.   Any experience or advice? 

I rarely shoot anything with the Ruger label on it but that's because they don't make what I need to shoot LR and ELR. But there are rules in place for standardized reloading safety.

7.62x39 is associated with two different groove diameters; .311" and .308" which makes knowing this diameter important. In a very short search for this information, Ruger only releases the fact that they have created a throat in some models which will accommodate both bullet diameter. Even a call to Technical services only yielded a response of it's ..., I think. So, if someone has the diameter of this rifle, please post it. Otherwise I suggest 'slugging' the barrel in any case in order to determine which diameter you have.

There is too much information to cover the argument regarding the safety of shooting larger diameter bullets in a smaller diameter barrel. The exceptions are many and there are too many variations to make an absolute decision. I match the bullets I use to the groove diameter of the barrel, period. No exceptions because I don't shoot much lead.

You can probably use your load of BLC-2 because it's so slow for this cartridge and bullet weight that you won't hit the ceiling of pressure even compressed. You will be wasting quite a bit of powder trying to make this work because it won't all burn in the short barrel. I suggest reviewing the above information to see if you might make a better decision about the powder you can use safely. Stick to the printed loads until you develop the ability and experience to improvise.

Best.

 

buddyb

Thanks.Good information