The first load I developed for my new 7RM loaded the 168 VLD over Retumbo powder. This produced 4 shot groups of 15" at 300 meters.

Next, I wanted to develop a load with the 140 VLD.

Now, when I went to load up more rounds with the 168 VLD, there is a 5-7 thousandths variance from one loaded round to the next due to the tip of the bullets not being consistent.

How do I set my die to achieve the original O.L.?

Bobby B.

What is your variance to the bullets ogive? With your .284 bullets, call it the .278 diameter location (close enough).
What most people want to keep consistant is the distance between the ogive and the lands, not the OAL.

Tailgunner,

I, too, want to keep the distance between the ogive and the lands consistent and am not concerned about overall length.

What I need to determine is precisely to where my seating die was originally adjusted so as to replicate the original ogive to lands distance.

Is there a specific tool I can purchase?

Bobby B.

15" @ 300 Meters ???. WHY WOULD ANYONE WANT TO KEEP THAT ???.

Doc,

Good eye. That should read 1.5".

I found my old notes and have solved my problem. The original load was seated .010" INTO the lands so I'll simply seat a round to touch the lands, measure it then back the bullet out and seat it in .010" less than touching.

Bobby B.

This thread makes a lot more sense now.

Why do want something else? The 168 bullet will be much less subject to wind drift than the 140. You might get more velocity, but what for? And the accuracy might not be as good.

LWD

Hey Bobby, Yes indeed there is a method which allows you to Duplicate the original Loading - if - you still have at least one of the original Bullets and have not readjusted your Seating Die. The instructions are written with the intent to change from OCL to ODL. It is fairly self explainatory, but if you have a problem with it you can send me a PM.

No new tools are needed if you have a set of 0.001" capable Calipers.

You do need to make sure those really sleek Berger VLDs do not let the Nose touch the bottom of the Seating Stem, or your distance from the Ogive to the Lands will never be consistent.

Best of luck to you.

Hotcore,

Your method and my method is one and the same. However, I did not test if the nose of the 168 VLD's were touching the seating stem. Never thought of it. Thanks for the heads up. I'll check it out.

Bobby B.

Bobby, variance in seating depth can be caused by variance in the finish and dimensions of the inside of your neck. When you are seating your bullets you can feel the difference in seating pressure. If you feel one bullet that is harder to seat than others then that bullet will have a longer OAL. The problem is exacerbated if you have a lot of bullet grip.

IOW if the inside dimension of your neck is .004" smaller than caliber then that is too much and your OAL will vary.

Lately I have been paying special attention to seating pressure and it has been paying off. I use a Lee Collet Neck Sizer in most cases which does not oversize the neck and provides approx .001" bullet grip. Also polish up the inside of the neck with steel wool on a 22 cal brush


and coat the inside of the necks with mica


The bullets go in slick and I have very consistant OAL measurements, both measured with a comparator and to the tip. It also pays off in velocity variation. The last 6 shots with my 338RUM chronographed 3191, 3182, 3182, 3189, 3189 and 3197 fps.

The great groups you got with the bullets seated into the lands also lead to the conclusion that seating depth consistancy is your problem since seating into the lands will negate the effects of inconsistant seating depth.

HC, is there any baling wire or duct tape in that antiquated method you are alluding to?

quote:

Originally posted by woods:
HC, is there any baling wire or duct tape in that antiquated method you are alluding to?

I know of no Reloading Procedure that can't be enhanced with a judicious use of Baling Wire and Duct Tape. Or Duck Tape if you are into taping Ducks!

The exact OAL you had with the original bullet can`t be found now with another, even from the same box. Bullet lgt varies even in the same box so you need to use one bullet for all set-up and measurments. A Stoney Point, Sinclair or other tool for measuring off the ogive is what you want. They will allow you measure any bullet ogive from case base which is the critical measurment when keeping a set distance from the leade.
As noted the seater must seat off the ogive and not the tip of the bullet to make any true measurments possible.

I either modify my seater stem or make one that touches closer to the ogive.
Butch