Re: 7.62x54R
Posted: 28 Feb 2018 18:47
Yeah, it is quite a jump. Based on my shooting, I'm a one caliber seating guy at a minimum. I'm not sure what cartridge they had in mind for the Speer, but it has the same issue with the 303 British. Not enough depth in the neck or too much jump.cj8281 wrote:Yeah, 3.038" isn't going to happen. I resized a case, checked it for trim (2.11") and then seated a bullet so the bottom of the bullet was even with the neck, 2.796". Pulled the bullet with a kinetic puller and then started the bullet in the case about an 1/8th of an inch. Chambered the round, sans powder and primer and I get 2.986". That Speer bullet is short and fat, 1.061" in length. Case neck measures .373" in length (roughly). So with the cartridge at 2.986", the bullet is only seated in the neck .185" so roughly 3/16 which about half way into the neck. I think with this bullet, maybe seating it to 2.830" or maybe 2.850". If the bullet was seated to 2.850" it would have about a .135" jump before engaging the lands. That is quite a jump.
I will run the data at 2.830" this evening, got to go next door and check on my dad now. At that length, the data will be still valid for the longer COAL (not the other way around though).
Not sure what the bullet in the drawing is other than the generic spec bullet for CIP. The weight would be on the spec sheet.cj8281 wrote:I think the bullet in your drawing maybe based on the steel cored bullet and that is why it is so much longer. I believe my military surplus ammo to be in the 147 to 155gr range.
It looks like IMR 4350 is generally about a grain or two less than the H4350 in most cartridges. Hodgdon's website shows H4350 at 55 grains but they lists the COL at 2.975. The bullet they list is SFT SCIR. Not sure what that one is. So 54 grains is not out of line, I probably wouldn't go much over 50 grains of IMR 4350. Its a plinking gun or a SHTF backup gun. The mold I have for it is the Lyman 314299.