bigcountry

Loading for my 7mm-08. I usually use my stoney point for finding the lands. But i loaned it out to another new reloader. So in a hurry to load some shells, I find this gun has a nice short throat. I tried the SAAMI COL of 2.8" but it won't chamber so I haven't done the split case method in years and years, so I figure why not. I was shocked to find it much more consistent than I did before. I measured three bullets with a sized case I modified with a dremel and measured 2.748 for bullet 1, 2.7445" for bullet 2 and 2.748" for bullet 3. i did it three times for each bullet. All bullets were 140gr gamekings.

I figure if I load to 2.740" I should be safe from pressure spikes. But thinking 2.735" would be safe. How much more do you set your bullet back when using this method. No I didn't do the felt tip pen. I have tried that too many times with wrong results. Boy I miss my stoney. I am concerned cause I know this is like me jamming the bullet into the rifling with my stoney which if I remember can be .01" more than if I was barely touching.

Roskoe

BC - I normally like to be either jammed into the lands a little (for target shooting) or backed off at least .010 - up to .020. If you try to seat too close to touching, some rounds will wind up actually touching and some won't (not good for accuracy) - due to variations in ogive and seating depth. So I would probably go with 2.735". Good luck getting your Stoney Point back . . .

trailer

Man you’re a nice guy. Can I borrow it next but you’ll have to mail it to me.

bigcountry

Well, trailer I loan it out often cause generally its something you only need to do once for a gun/bullet combo. After that, just measure throat errosion.

Mossy had it for a month but didnt' like it.

vangunsmith

The Nosler com. just did a big research on this,and found out that the distance between the rifiling and the bullet does not affect accuracy. It ONLY increased velocity and Breech pressures. tho;ught i,d pass this misnomer along. At least thats what they say. vangunsmith

Briman

I'll have to try this tomorrow.

I'm trying out some 168 gr SMKs in a schmidt rubin rifle- can you say extremely short throat?

Stoney point doesn't make an oal measuring case for this cartridge yet and I don't feel like going through the trouble of sening in fired brass and paying the $s for something that I will only use for 5 minutes.

bigcountry

Well that will be thier little secret nobody in the shooting industry knows.

So vangun, do you have anything to add to the original question or you don't know?

Mr. Longbeard

Can some one explain the "split case method"???

bigcountry

long, reloaders like to be close to the rifling. I have found you will get best accuacy close in some situations. The claim I find to be true is the bullet will ahve less jump out of the case and will wobble less, due to neck tension variations, seating variation, and will hit the rifling much more straight and therefore the bullet will be much less destorted coming out.

So you can use a tool like i have called stoneypoint AOL guage where you take a case and put it in the chamber with the tool, and you push on the bullet until you just feel it hit the lands and grooves. Take it out and measure the COL or ogive if you have a comparitor.

But the poor mans way is taking a sized case and taking a dremel tool and cutting the neck so you can put a bullet into it but with alot of resistence. (Too little resitence and the rifling can grab onto it and pull it out of the case some and false values.) Chamber the round in your bolt gun and carefull remove it. Be careful not the lest the extractor mechanism shove it agaist the action. Not measure the COL fo the bullet/brass combo.

This is handy in my situation where the throat is much shorter than SAAMI specs.

I don't want to be into the rifling. You can get a pressure spike and that will cause pressure signs before you reach your full potiential velocity.

Roskoe

BC - just in the last couple of years the folks at Sierra have recommended that, if you are not getting good groups with the bullet seated fairly close to the lands, to try seating them deeper. It's kind of a "last resort" solution, but sometimes it works. In my 6MM-284 that I just re-barreled with a Jeff Lawrence 1:9, the 105 Hornady A-Max is shooting right at 1/4" with the bullet seated about .075 back from the lands. I would have seated it closer, but the magazine length of the short action Remington limited me to 2.810 - so I tried it at that length, and I'm not wanting to change anything now