COL Using the Split Case Method
 

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.

RE: COL Using the Split Case Method
 

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 . . .

RE: COL Using the Split Case Method
 

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

RE: COL Using the Split Case Method
 

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.

RE: COL Using the Split Case Method
 

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

RE: COL Using the Split Case Method
 

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.

RE: COL Using the Split Case Method
 

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?

RE: COL Using the Split Case Method
 

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

RE: COL Using the Split Case Method
 

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.

RE: COL Using the Split Case Method
 

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 :)

RE: COL Using the Split Case Method
 

I agree whole heartly with them. It worked out great in a 300RUM I had. I was shooting A-Frames, and getting 2MOA groups, I moved it back and back and back from 3.62" COL to 3.55" and got it down to subMOA.

Alot of poeple Roskoe has this conception that this changes harmonics and all that, but you have also changing the load effectively. And will be increasing pressure for most powders the deeper you go.

RE: COL Using the Split Case Method
 

Now when you cut the neck of the case. How much do you cut away. Half the neck or less than half. Or do you just have to keep cutting them until you find the right cut???

RE: COL Using the Split Case Method
 

You cut length ways. What you are trying to do is be able to let a bullet be pushed down in it. I cut down the neck and a little bit in the shoulder. I will take a picture and send to ya tonight.

RE: COL Using the Split Case Method
 

I'm not convinced that seating bullets near the lands does anything good for accuracy. I've played with it a bit in the past and found that its more of a waste of good bullets and gunpowder than its worth. I Use a OAL guage to figure out what my max length is so I don't mistakenly seat bullets any closer than 0.020" to the lands, I prefer farther away if possible with jacketed bulelts.

Two of my most accurate rifles: a 1903A3 likes cast bullets engraved tight into the rifling, a 1896 mauser that has so much freebore that getting a bullet anywhere near the lands would be impossible.

RE: COL Using the Split Case Method
 

Well, I never posted this to find the most accurate or whatever. I have been successful on doing that with quite an array of rifles as you probably have also. I rarely find a rifle with such a short throat to even worry about this. I posted this cause I am without my stoney until my buddy sends it back, and I was wanting experience with people who use the Split case method. Because the throat is so short.

And its no secret to any reloader that jamming in the rifling can cause you to show pressure signs way before reaching the velocity potential.

RE: COL Using the Split Case Method
 

If you dont have a stoney point gauge then you can take a bullet and put it in a case just enough for it to hold, color all of the bullet that isnt in the case and push the cartridge into the chamber, pull it out and if the bullet is stuck just take a peice of a cleaning rod and drop it down the barrel, re-seat the bullet to the mark the case left on the bullet when it got pushed into the case and measure the length. This usually gets your OAL length from the ogive. I sometimes do this because I dont have a OAL gauge. I usually just trim the cases to an exact length and maybe .004" shorter on accident, then I'll seat the bullet to the same length as a factory load of the same bullet weight then due to each bullet being longer or shorter I'll re set my seater die to compensate for each bullets length. That way each cartridge is the exact same length.

RE: COL Using the Split Case Method
 

As I mention in the orginal post, they techniques seem worthless to me as yes, I remember first time reading a reloading manual and them telling me to do that.

RE: COL Using the Split Case Method
 

I seat everything .030 from the lands. This almost always works well for me. If it does not work then I start fooling with seating depth. I don't reload for the pure joy of reloading like I did 35 years ago or so. Just reload because I have the stuff and its cheaper. I have never had a length guage.

RE: COL Using the Split Case Method
 

yep me too, I usually always start @ .030 Id say 4 of the 7 rifles I shoot are .030 and the other 3 are .035-.040.

RE: COL Using the Split Case Method
 

Mossy, I know one rifle you don't seat .03" from the rifleing.