9x18 Ballistics

Bad Posterier Round

That "Silver Bear" 120gr round? It say here in this book that Muzzle Energy is computed (MV squared / 7000) / 64.32 X BW. Muzzle Velocity (squared) divided by 64.32 times bullet weight.
1126 squared = 1267876
1267876 divided by 7000 = 181.1251429
181.1251429 divided by 64.32 times 120 = 337.9 FPE

Factor in the way "goldenloki" gel-tests show the expansion of the projectile and you got one nasty piece of work in the S-B 120. On the box of my 90 gr. Federal "Classic Hi-Shok," which I've been carrying, it says they have a ME of 195 FP at 990 FPS. I've never fired Silver Bear, and know nothing of their reliablity, but for sheer "oomph" and authority I think I'm gonna order a cuppla boxes.
Tom K.
 
Apologies

Shoot--I just realized it was Snowdog what posted the Silver Bear pictures not goldenloki. My apologies and groveling. Trying to do that math done "fouled" up my head fer sure. (Substitute the word of your choice for "fouled.")
Tom K.
 
Tom...another equation for figuring Muzzle Energy...try this
( Muzzle vel (fps) x Muzzle vel (fps) x Bullet wt (gr.) = total, then divide the total by 450240 = Muzzle energy....shoot well
 
Yeah, I've heard of the Silver Bear stuff.

I don't consider it to be a true Mak load--more of a Mak +P load. Scuttlebutt is that you'd better put a heavier spring in your Mak if you intend to shoot a lot of it.

Same reason I didn't use 9mm +P numbers in my comparison. There are a million ways to do the calculaton. Even Federal loads at least 3 bullet weights in 9mmP. I just picked what I considered to be representative loadings. Not +P, not light loads, not heavy or light bullets. I tried to make it more or less what you are likely to get if you go buy a box of plinking ammo of each off the shelf of your local gun store.

However, your argument that both .380 and 9mm are downloaded for the American market is certainly not far off the mark.

Cheers,

John
 
John,
I look for the most potent ammo possible for my .380..for the reason that its a .380 and just about any load over 200 FPE
is on the +P border. After reading up on the Silver Bear Mak.
load..I found a 147 gr 9mm that has 470 FPE...good lord...I want
to try some....Hotter than corbon, which is the hottest I have shot or heard about in the states.

I checked out a bunch of links that are tied to Makarov.com and
read up a little more on the Mak. loads. They recommend highly
to not us any ammo that has more energy than approx. 250 FPE
on a regular basis, even with stouter springs.
The Silver Bear ammo, especially the HP's sounds like its generally loaded as hot as they can go...maybe too hot for some guns. I know NATO pressure limits are higher than ours and may
be the reason for the S.B. Wolf actually is hot enough they dont recommend it on a constant basis. Kinda strange.
Just more info I found.
Peace and Shoot well
 
You must log in or register to reply here.
Back
Top