.308 test results

[waco]

So I'm working with a couple different bullets to try and work up a load in my Rem 700 in .308

I got out over the weekend to shoot a little. I got my speeds up a bit. Enough to get me out to 500 yards, I THINK.

The two loads that showed some promise where the Lee 312-155 and an NOE copy of the 312299

Both bullets were sized to .311" The Lee was powder coated and the 299 was lubed with 2500+

LC brass and CCI LRP were used all around. I'm going to weight sort brass next time as I think this may have been part of the problem with the groups having odd flyers. The brass is anywere from '03-'15

Anyway. The Lee was loaded with 36gr of IMR 3031. This was probably not a great powder choice as it's a bit on the fast side. Avg.fps=2281 s.d=13.3

The 299 was loaded with 41gr of IMR 4831. Avg.fps=2040 s.d=11.2

And the testing continues.......

 

[Rick]

Hhmmm . . . The last pic, front driving band looks to have been chambered but I don't see any rifling marks on the nose. Did you place the nose of a bullet in the muzzle to see how loose it is? Without any support of the nose it will tip on it's flight down the barrel and could very well account for groups.

 

[fiver]

you'll have more to play with in about 3 day's.

 

[fiver]

I just looked at the numbers.
umm you can't shoot under 2" groups at over 2,000 fps.... I don't know what your thinking there.

 

[waco]

Rick. These have a .302" nose. I'll try putting the nose in the muzzle.

 

[waco]

The 1.3" group is the 299 and the larger group is the Lee.
These were shot at 100 yards BTW.

 

[fiver]

I don't think I could chamber a 302 nose in any of my 308's.
301 is tight enough, but none of them are Remington's either.

 

[waco]

I just put a bullet in a fired case and chambered it. It measured about .013" longer than the 2.900" I had those loaded to.
Putting the bullet nose first in the muzzle it stopped pretty much at the ogive.
Seating and chambering the dummy round really didn't leave any marks on the nose either.

 

[Ian]

Dang, don't you have any Varget or 4350? I'm impressed with the SD from the 4831, though.

A little birdy is chirping: this is useless without a pound cast.

 

[Rick]

A pound cast may well be in order, the .302" nose doesn't enter the muzzle but chambers and leaves no marks.

 

[Brad]

Sounds like a well worn throats to me. A gentle ignition my be good. Let the bullet get pushed slowly into engraving the rifling.

 

[fiver]

that's why the 4831
ah jeez now I'm underlining stuff woah got it... damn dog.

 

[Ian]

Hi, Jax.

.311" bullets in a .308 managing to group together at 100 yards was my clue to worn throat. Normally you need to go .3095-.310" to keep from raking off one side of the bullet on the sharp, tight throat entrance.

The other good thing about 4831 is you can use it with the heavy bullets all the way up to the pressure limits of the cartridge without having to mess with anything else. There will be some spots along the way up that it won't group for beans, but that is true of any powder, just watch the patterns on the target. Do the rest with alloy changes and seating depth....and whatever else it takes. The bullets already say they will shoot, but you can't just keep adding powder and hope it will stay together because it won't.....starting in about 100 more fps. That's when you get to start tweaking things and getting your groups back, then add more powder until it falls apart, tweak some more until you figure out how to fix what went wrong, add some more powder, until.....well, I'll let you figure it out 'cuz that's the only way anybody ever seems to learn how to load cast bullets where they will group at HV.

 

[fiver]

I thought about tossing some 314299's in the box, they make almost 304 on the nose.
I guess I should have just done it.

 

[waco]

I know these 700 have long throats. My buddy and Dad both bought new ones in .308 as well. None of us could seat a 175 SMK out long enough to touch the rifling. Book says 2.800”
I load to 2.900+” and still don’t touch. I don’t think the gun was shot much before I got it and I know I haven’t put that many down the tube. Plus the new ones acted the same way.

 

[Kevin Stenberg]

Ian are you saying IMR 4831?

 

[fiver]

they both work, I use the SC version in my 308 loads.
Accurates 3100 was good too but absolutely had to have a filler to make sure it was kept in place to do it's best work, and rl-19 has potential in the 308 case family it is my one and only 358 win powder.
IMR powders have worked better for me in reduced loads as a general rule though.

 

[waco]

So I just loaded up a dummy round in a trimmed FL sized case. Just like the ammo was loaded. The load was 2.900"
After running it into the chamber I removed it and it measured 2.873"
These were a tight fit on the range as I remember it, as was this one. You can see where the rifling engages the nose, it's just very hard to get the light right for it to come across in the pics.

.311" bullets in a .308 managing to group together at 100 yards was my clue to worn throat. Normally you need to go .3095-.310" to keep from raking off one side of the bullet on the sharp, tight throat entrance.

I get good groups sizing for my 300blk at .311" and it's a new rifle. Maybe I'd have better groups at .310"? I should by a size die. The ..311" is the only one I have at this time.

 

[waco]

 

[waco]

Dang, don't you have any Varget or 4350? I'm impressed with the SD from the 4831, though.

Yeah. I have both of those. The 4831 in the .308 was suggested to me by Fiver. It shows promise.