Segregating .338 SMKs 300gr What priorities?

[AJ Peacock]

I want to start segregating my 300 gr SMK's. I have 1000 of them.
What are the best priorities? These will be used in my 338AM this summer.

Bearing surface first ?
base to ogive second ?
Other measurements ?

For each of the above measurements, how large should the group be? .001"?

Once they are segregated, then I will weigh them all to find any 'out of norm' weights. I weighed a bunch and they were all from 299.9 - 300.1.

Thanks,
Don

 

[royinidaho]

I tried that and it got real boring real fast. Weights were as you stated so forget that.

I guess I'd go with bearing surface only but that is a bit of a bother. So maybe base to ogive.

Short answer though, is just shoot 'em.

In my RUM and US-869 I'm getting single digit ESs which seems to be what's important as the groups can't get any smaller and am using just 'out of the box' SMKs.

 

[Jimm]

What Roy said , times 10

especially that " just shoot em part "

Jim B.

 

[Buffalobob]

But he don't got no gun! All he has got to play with is boollits. /ubbthreads/images/graemlins/grin.gif

Poor AJ will be crazy before Kirby gets his gun built.

 

[goodgrouper]

Bearing surface measurements pick up 99% of errors.
Base to ogive measurements pick up probably 97% of errors.

If you have a way to measure by bearing surface, it is best and will negate having to measure base to ogive for the most part.

I segregate all my bullets (including the incosistent 300 grain MK's) into piles of .001" variation and then load and shoot them in these batches.

Weight on your batch of MK's is the best I've ever seen for the 300's. I wouldn't worry about it.

 

[Chawlston]

I agree with GG. If you guys will get two ogive noses from Sinclair, they make an excellent bearing surface measuring device.

Just as an example the Berger bearing surface and the Wildcat bearing surfaces on the 210gr 30 caliber bullets are within .003" of each other on the batches that I have.

Anyway, it is very quick to measure them.

James

 

[pinshootr]

Don don't waste your time with those big old long bullets send them to me and I'll sort them out for you LOL Tod /ubbthreads/images/graemlins/grin.gif

 

[AJ Peacock]

[ QUOTE ]
But he don't got no gun! All he has got to play with is boollits. /ubbthreads/images/graemlins/grin.gif

Poor AJ will be crazy before Kirby gets his gun built.

[/ QUOTE ]

Thats about right.

I did some searches and found a post by Shawn Carlock that said he did a Base-Ogive measurement to segregate by .001" first, then does a bearing surface, then either selects the best Meplats, or trims them to be consistent.

Well after about half dozen attempts at a repeatable method for measuring these stoooopid booolits last night, I used my stoney point tools and my calipers. I put the .33 ogive measure on one caliper blade and the .35 headspace tool on the other blade. I then had a repeatable way to measure base to ogive. The .35 headspace tool, held the bullet straigt, so I could get a consistent measurement on the .33 ogive gage. Without it, my measurements would vary by +- .001", which is not what I wanted /ubbthreads/images/graemlins/wink.gif .

Here are my results on the first box of 500.

Actual number of bullets in the box was 504.

The actual length is less important than the relative length for me to segregate. So the 'actual lengths' might be a thousandth longer or shorter. I was more interested in a repeatable method for sorting than the actual length.

.970" 122
.971" 230
.972" 120
.973" 26
.974" 3
.976" 1
.977" 2

Looks a lot like a bell curve with a test for the short ones at the factory.

I figured the 338AM would cause my shoulder to hurt, but I figured it would be AFter I shot it!



Doctor: "So, you're complaining about your shoulder and elbow hurting?"

AJ: "yes, I've been measuring 1000's of bullets for length at an accuracy of .001" or better ..."

Doctor: "Nurse, I think I need a Pysch consult here. AJ, go with these gentleman in the white coats and they will take care of you." /ubbthreads/images/graemlins/shocked.gif

Don

 

[AJ Peacock]

I thought someone might be interested in the breakdown of the base-ogive and bearing surface measurements for the first box of 500 .338 SMK's.

I'd be interested to know if my distributions are similar to others here on the forum. I figure I'll weigh them to remove any outliers prior to loading and after any Meplat trimming I might perform.

Base-Ogive, total, (bearing surface length x number found) ...

.970" 122 (.728x51) (.729x34) (.730x26) (.731x11)
.971" 230 (.728x72) (.729x51) (.730x77) (.731x29) (.732x1)
.972" 120 (.729x4) (.730x46) (.731x26) (.732x23) (.733x19) (.734x2)
.973" 26 (.731x5) (.732x14) (.733x2) (.734x1) (longerx4)
.974" 3 not measured
.976" 1 not measured
.977" 2 not measured

Shown by Bearing Surface x number of bullets
.728 x 123
.729 x 89
.730 x 149
.731 x 71
.732 x 38
.733 x 21
.734 x 3
Other x 10

 

[longrangebo]

I guess I messed up, I only have a handfull of the 300s left and none of the deer or baer I shot in the last 7 years knew it. I never measured 1 of them /ubbthreads/images/graemlins/laugh.gif

 

[steelhead]

When I went to pick up my rifle that Shawn built me, I asked him to show me what he does to seperate his .338 300 grain bullets to get the best accuracy. Anyway, when I got home, I was so excited to shoot my rifle that I didn't bother segregating my bullets, I just loaded them up and headed to the range.

Shawn provided test targets that he shot with my rifle. One of them had a group of .242 inches. My first three shots I made from this rifle duplicated that group. I got a .241 inch group. I've never segregated my bullets since. Even if these groups open up to twice this, from not segregating them, I'm happy.

 

[goodgrouper]

Deer or bear wouldn't know the difference, you are right. The only time they (or you) might see a difference is when shooting to and past 1000 yards.

At 2000 yards, I once shot two bullets that went the same speed but had .002" variation in bearing surface and they landed about 25" from each other vertically! /ubbthreads/images/graemlins/shocked.gif

 

[Chawlston]

[ QUOTE ]
I guess I messed up, I only have a handfull of the 300s left and none of the deer or baer I shot in the last 7 years knew it. I never measured 1 of them /ubbthreads/images/graemlins/laugh.gif

[/ QUOTE ]

If you had segregated them they when the animals got hit they would have known it. /ubbthreads/images/graemlins/wink.gif

James

 

[longrangebo]

I forgot to mention that many were shot between 900 and 1400 yds. , the conditions, sutch as wind , up hill ,down hill, and light have a lot more infulance at that differance than anything else! /ubbthreads/images/graemlins/grin.gif