At the end of this post Gary and I made a bet regarding the spitzer I have been shooting through my .308:[www.airgunrendezvous.com]
Well, here's the first part of my testing, before and after pictures of the spitzers shot into the pool, to check out the engraving:
Before:

After:



Gary, over to you to analyse the results......but, well, as I see it, and as you predicted, still plenty of engraving on the .308 slug
Cheers
Neil

Hi Neil,

Great documentation there. Actually, as you can see, there's nearly no difference. You could still go smaller, if you had a sizing die for it. That's still alot of bullet deformation from the rifling. You need a ringed slug ... like .... hahah

And I need a swimming pool .... hahah.

Gary



Edited 1 time(s). Last edit at 03/25/2010 02:13PM by barnespneumatic.

Neil,

Are you sure those slugs are the size they are labeled? Since they don't have sizing die marks, they must drop from the mold right on size. That's certainly possible but a little unusual.

Man, that is excellent accuracy!! .5 in group at 100 yards is almost unbeleiveable for bigbore. Neil, do you know its averaged group? It should be close to that size, just curious. Good job!!

Hello Peter
I haven't measured an average for groups, but on the right day this gun can shoot some good ones. That sub 1/2 incher was with the HP's, below is a sub incher with the spitzers

I'll try to better this as part of Gary's challenge!
Cheers
Neil



Edited 1 time(s). Last edit at 03/26/2010 06:22PM by neilmcp.

Jerry, you had me worried that I might have mixed up my slugs, so I repeated the test. Here are some of the .308 sized slugs. I think I can see a bit of dragging on the rings at the rear:

Now here's one of those two shot into the pool an hour ago:

Pretty similar to the other test I think.
The barrel is supposed to be spot on .308, so if the body of the slug is .308 already it won't show sizing marks, and seems to slide through the grooves relatively untouched in the swimming pool version....
Mind you, these are Lee mold slugs described ae 312's, so who knows
Cheers
Neil

Hi Neil,

Not to pick, but do you mean the "bore of the sizing die" is supposed to be spot on .308"? It reads "barrel".

Also; you can see that this slug is "scrounging" the bore of the barrel. It's not only being cut by the rifling, but the sides of the bullet are dragging along the bottom of the grooves. You can note, from about half way down the bullet to the base, drag marks on the body of the slug.

I'm not saying if that's good or bad. I'm NOT starting another nightmare like that bullet twist thread!! hahah.

Gary

Sorry, I need to be a bit more precise with my terminology!!
I now see the scrounging you are referring to (note to self: Do something about your eye for detail while you are working on the terminology...). As to whether it is a good or bad thing, I guess it is a trade-off between a good seal and extra drag...??
Cheers
Neil

Hi Neil,

The party line is that you need a perfect seal.

The Gary line is that to squeeze thru a thousandth gap between the bottom of the grooves and the slug, takes more time that the slug has in the bore. But ... I'm not starting anything. haha.

Gary

When life allows, I'll send you some slugs to try. Since you actually shoot, and you are just around the corner ...

I'd be honoured to try some of your slugs one day Gary

Dang wind stopped me from doing "the test" this weekend.......

Cheers
Neil