Case Tension, Trimming, Primer Pocket Squaring, Flash Hole Deburring Range Report

[918v]

OK,

So I tested my two theories today, using the finest of components and pistolas. In the red corner stood a pile of rounds assembled from benchrest prepped components sorted by a subjective assessment of case tension. There were three groups: light, moderate, and heavy.

In the blue corner stood a pile of rounds sorted by OAL. There were six groups: 1.098" through 1.103" in .001" increments.

The results blew me away.

Brace yourselves.







































INCONCLUSIVE

:banghead:



Here's what I observed:

The red corner rounds groupped the worst. In fact, the moderate tension batch produced a 1" group at 15 yards that looked like a boomerang.

The blue corner rounds produced the accuracy I longed for. Nice half-inch or better five shot clusters. The problem is that the POI of 1.098", 1.099", 1.100, 1.101, 1.102, and 1.103" batches was in the same spot on the target, or at least within a quarter inch. Further, I observed POI change depending on how tightly I held the gun, and all shooting was from a benchrest.

I conclude that sorting is for suckas.

[BigSlick]

We already knew dat 918

But thanks for confirming dat for errybody.

You can see a some difference when sorting by OAL and weight with bullets 165gr an above, but below dat, in pistol, not worth da effort.

Try it, you a see

[AdamN]

If ya wanna learn anything you need to shoot farther than 15 yards. For most off the shelf guns 25yards is enough. If youre getting 1" groups @25 then back up to 50 yards. If ya get 1" @50 then ya got a winner.

Here is a pic I nabbed from another forum. Ouality gun, 9mm off the shelf ammo components. ALmost 1/2" at 50 yards, 10 shots.
http://img.photobucket.com/albums/v136/a1acp/DSC05663.jpg

[918v]

I did too, just refused to accept it. So I wasted a week's worth of free time.

[918v]

I can't shoot at 25 yards. I can't discern the 6 o'clock of the target at that range.

[918v]

http://img.photobucket.com/albums/v136/a1acp/DSC05663.jpg


But he's got an electronic sight.

And his barrel twist is slower than 1-10"

The best a P210 will do at 50 is 1.5" with 147gr stuff.

[AdamN]

The dot dont make the groups any tighter, My point is that the 9mm as is can shoot. A few years ago a lot of guys would have laughed at ya if you mentioned 9mm and 50 yard accuracy. After a lot of guys kept experimenting there are some combos out there that have shooters clamoring for a 9mm

[layusn1]

Hmm, I thought all of those steps were supposedly wasted in handguns? I do them for my rifle rounds though. I haven't done any without doing those steps to do a comparison.

[918v]

The dot dont make the groups any tighter

It is far easier to find the center of a bullseye using one of those red-dot sights than to find the 6 o'clock consistently with military serrated ramp teeny ****ty open sights.

[MullahElRon]

I thought all of those steps were supposedly wasted in handgunsThey is wasted, but we want to keep 918v busy instead of goin' all ape loco and other stuff that get him put away.

[918v]

I think I'm just gonna have to build me a 9mm benchrest rifle. A slightly modified 223 action with a 16.25" straight taper Krieger barrel and a 60x scope should be the ticket.

[Steve Koski]

I don't think that's a 10 round group in the picture...

[colorado4wheel]

It is far easier to find the center of a bullseye using one of those red-dot sights than to find the 6 o'clock consistently with military serrated ramp teeny ****ty open sights.

If thats what you got for a gun, why you bothering with all this obsessive detail for. Get good sights for crying out loud.

[918v]

You can't mount a red dot on the slide of a P210. I don't wanna hack into it either. I did get a pair of adjustable sights for it, just need to take the time to install them.

[Mogollon]

For accuracy testing such as you are doing, I would suggest a T/C contender. Barrels have been made in lots of calibers, including 9mm. Could be made into a carbine too.

[Tree Rat]

I did too, just refused to accept it. So I wasted a week's worth of free time.

No you didn't.....you just had to know.

I wonder now that you decided OAL sort is the way to go, what the groups would look like without all the prep and just shoot the sorted by OAL rounds?

What was the load by the way?

TR

[918v]

The load was 147gr XTP on top of 3.3 grains of Bullseye, primed by FC-100.

I The only problem with all this prep work is that it may be completely overshadowed by the influence of grip on POI. If I am unable to grip the gun consistently enough, I may not see the miniscule benefits of benchrest prep.

I do like having all the cases trimmed to .750". It makes for a very pretty taper crimp.

[Oreo]

I think it was already said that there's no possible way that you'd be able reduce the human factor enough to justify your research. Ever seen Mythbusters? You need to build one of their rigs that hold the gun for you & pull the trigger with a string. That's the only way to see these small changes from a pistol.

[Crazy4nitro]

All this leads me to My experiment thats coming soon...

My Reloads VS WWB.

Since it has been a VERY long time since I have even bought Factory Excuses I will get to see how my Cheapo reloads Match up to the Heights of the Caliber Corner Gods almighty Money wasters.

This could get real interesting.

'Nitro