.38-55 chrony work

[Paul5388]

I did a little chrony work today with the cut down .38-55 on the BC stock and receiver.  If you're interested, it can be seen here.

[handirifle]

Interesting post.  I read the same thing somewhere (can't remember) about a guy that discovered this same phenomonon while testing proof loads for an ammo company.  He did it by slowly rotating the ammo.  He found that when he did this and stopped with the bullet up every time his loads were so consistant is was almost scarry.

Huge difference when compared to the loads inserted into the chamber with the bullet pointed down, moving the powder away from the primer.

As for the 30-30 vs. the 375 brass, nice to see proof, but not as suprising, since the 375 brass is quite a bit thicker at the base than the 30-30 or the 38-55.

[Paul5388]

Obviously a pretty near full case of a slow powder isn't going to exhibit much powder postition sensitivityty.  It's mostly going to be a problem with low level/reduced loads.  Most of the time it will never be noticed until that unexplained miss during hunting season.

I suppose I'll have to go out of my way to test for powder postition sensitivity in the future, especially with the numerous Blue Dot loads I use.

[Paul5388]

Here's a copy (it shows up better this way than a quote does) of the results of some Blue Dot loads comparing normal insertion of the cartridges with lifting the barrel before shooting.

"OK, here it is structured just like I said before.



It has to be remembered that the first shot or two are actually fouling shots (they're numbered on the target), but even so, there just isn't much difference in the shots. It may be my crumby shooting more than anything else! However, it certainly wasn't a 12" group either (like they got at http://www.gmdr.com/lever/lowveldata.htm).

From the POI, I would say these are all in the 1150-1250 fps range, very much like what I shot yesterday at that velocity.

BTW, the total group size is 2 3/8" at 50 yards. That's not great, but it includes the fouling shots and each set of three shots made 1 1/2" groups.

I should have mentioned that the burn was much cleaner with Blue Dot. There's very little ash left in the barrel."