When do you not have ENOUGH bullet seating depth?

[copterdrvr]

Just got back into reloading after about 10 years and doing some re-learning.

I've put together some 168 grn Sierra Matchking loads with 39.5 grains of 4895 which was my pet load in my Model 70 HBV 308-and good to see it still is!

Picked up some 155 grn Sierra "Palma" HPBT match bullets and put together a few loads to try next time at the range.

I set these bullets to the same C.O.A.L. as the 168 grainers and I know that the 155 grn bullet isn't fully supported in the neck of the cartridge like the 168 grn bullets.

Is this going to be a problem? The break of the boat tail on the 155 grn bullet is only about half way down the neck. The very butt end of the bullet is even with where the neck of the case joins the main case body itself. Is the bullet not supported enough in the neck of the case? I neck resize only.

Thanks for any info.

 

[Sniper Uncle]

Rule of Thumb is: You should have one caliber seating depth. IE. 30 caliber should have .308" seating depth.

Some one correct me, but I believe that this would not count the boat tail if it is a shaped projectile.

 

[No1]

I believe it would not include the boat tail.

I think the most important aspect of a good bullet/neck purchase is to prevent the bullet from becoming misaligned during handling between loading bench and shooting bench or field. I wouldn't worry too much about it if shooting a single shot or bolt gun, I have loaded 40g Vmax in a 22-250 and they barely enter the neck at all and shoot 1" @250.

 

[copterdrvr]

That makes sense both ways-the cal. depth and not counting the boat tail as it doesn't come in contact with anything. Kinda adds a lot more free bore if I do it with these bullets.

My HBV is at 3.300 inches to kiss the lands with the 168 grn Match King and I've been loading my current test batch at 3.270 which seems to do best with this powder and bullet combination.

This ammo is all fired from a bench and I have single round bench magazine followers in both of my bolt actions so no magazine feeding!

 

[Layton]

Not sure if this helps but I load really long with my 6.5x55 and 140g hybrids. I don't quite have a caliber seating depth. .241 vs .264. I f/l size with a bushing die and unscrew the bushing nut so that I only size the portion of the neck that actually comes into contact with the bullet and stop. It's enough to hold the bullet tight with .002" neck tension. I had it chambered specifically for the 140s with a .010" jump and set my dummies up like this. My smith said it was fine. Bad pic below.

edt: I can mag feed.

L

 

[Fuzzball]

If your bullets fall out before you can get the cartridge chambered, seat deeper.

A "caliber deep" sounds smart, most 'common wisdom' nonsense does, but quite a few cases don't have necks a caliber long.

 

[copterdrvr]

Thanks all for the info-looks like I'll stop worrying about it and go shoot the damned things and see how they do!!!

 

[JGorski]

Just got back into reloading after about 10 years and doing some re-learning.

I've put together some 168 grn Sierra Matchking loads with 39.5 grains of 4895 which was my pet load in my Model 70 HBV 308-and good to see it still is!

Picked up some 155 grn Sierra "Palma" HPBT match bullets and put together a few loads to try next time at the range.

I set these bullets to the same C.O.A.L. as the 168 grainers and I know that the 155 grn bullet isn't fully supported in the neck of the cartridge like the 168 grn bullets.

Is this going to be a problem? The break of the boat tail on the 155 grn bullet is only about half way down the neck. The very butt end of the bullet is even with where the neck of the case joins the main case body itself. Is the bullet not supported enough in the neck of the case? I neck resize only.

Thanks for any info.

I seat the 155 & 168 Amaxs to pretty much the same depth, 155s are actually .025" further out and I don't have any issues with accuracy. If I can I like to have the pressure ring or the start of the boattail right even with the neck shoulder juncture.

 

[copterdrvr]

Not sure if this helps but I load really long with my 6.5x55 and 140g hybrids. I don't quite have a caliber seating depth. .241 vs .264. I f/l size with a bushing die and unscrew the bushing nut so that I only size the portion of the neck that actually comes into contact with the bullet and stop. It's enough to hold the bullet tight with .002" neck tension. I had it chambered specifically for the 140s with a .010" jump and set my dummies up like this. My smith said it was fine. Bad pic below.

edt: I can mag feed.

L

Thanks for the photo-forgot to mention this is pretty much what I'm seeing with my load setup and the 155's. The only difference is the "heel" of your boat tail round is alittle longer than mine but since it doesn't touch anything-no matter. Thanks all for the comments!

 

[mb3]

I generally load so the ogive is .02 off the lands. This generally means I have min seating depth. I would guess that as long as the bullet is sercure, and you are able to feed the round, min seating depth is not as important as max seating depth.

 

[witchhunter]

I wouldn't worry about COL as much as ogive to lands, unless you are trying to feed from a magazine. If you are, then mag length is probably going to be your limiting factor. You might find that seating depth is important with certain rifles and barrels. If you are using this for targets only you can single feed ammo and seat to whatever depth it likes.