Velocity 16.5 vs 22 inch handi Maxi

[petemi]

I finally went and did it.  Here's the ammo used, all factory which did not impress me with its consistency.

.38 Specvial (+P):  Federal Hi-Power, 125 gr. JSP

.357 Magnum:  Blue Star 158 gr. XTP

.357 Maximum:  Precision Cartridge 180 gr. SJHP

16.5 Inch Barrel:

.38 Spec.:                1191       1195        1178
.357 Mag.:               1714        1662        1722
.357 Max.:               1908        1894        1901



22 Inch Barrel:

.38 Spec.:               1134         1162        1178
.357 Mag.:               1668         1630        1754
.357 Max.:               2019         2042        2010

There are the figures, read em any way ya want.  The interesting thing is the .38s were faster in the short barrel.  The Mag and Maxis suffered a loss in the 16.5 inch barrel.  Not enough for me to worry about.

Hey Tim, almost forgot, didn't even blow up the Chrony

Pete

[snapcrackpop]

So next time you're going to do it with reloads, right? 

[NFG]

Excellent example that pistol rounds are designed to use faster burning powders which burn in shorter barrels, i.e., 38 Special - 2" bbl, 357 Mag - 4", 357 Maximum - not sure exactly but I would guess at least 8"...while rifle rounds "usually" use slower burning powders and require longer barrels to completely burn...that statement is a GENERALITY...NOT CAST IN STONE.

The only way to know for sure what is going on is to actually do the chrono testing with different burn rate powders.

It would be interesting if you did the same tests with your own handloads using the different pistol and shotgun powders and the SAME weight bullets...that would give a truer picture.

Not to make to fine a point, but I don't a lot of inconsistency...the velo spreads are really very close...standard deviation for the 38 Spec is about 8.9 in the 16.5" bbl and about 22.2 in the 11" bbl...not really too bad at all...wish some of my varminters were that close.  
 
Luck

[petemi]

After I was done, I shot some of my reloaded .38, 158rg JHPs and they ran a lot tighter at the very high 1100s to just a little over 1200 fps.  That was out of the shortie.  I gotta love that rifle.  I got together with a couple of other gun nuts last night.  They saw and handled the rifle and both volunteered to steal it, knowing it's not for sale.

Pete

[Spanky]

Great job Pete... the numbers for the 38 are pretty surprising from the short tube.
A little off topic but do you think the same trend would occur with a short 44 mag? I've been thinkin' of givin' mine the chop.
Oh and good job not shootin' the chrony.



Spanky

[NFG]

Closed breech shooters always do much better with pistol cartridges than in a similar length barreled pistol.

Compare a 44 mag in a T/C against say a Ruger Super Blackhawk and the T/C wins hands down most of the time...even better in the NEF.

Some rought numbers with H110, ~equal powder amounts for all, ~equal pressures - 38,300 CUP, 265 gr bullet...

4" Universal receiver...1140 fs/765 ftlbs
10" T/C...1360 fs/1088 ftlbs
14" T/C...1398 fs/1150 ftlbs
20" Win 94...1623 fs/1550 ftlbs

Lots of things to think about.

I really like my 16.5" 17 FB and 6mmBR...for varmints...my 20" 375 H&H  is handy but makes a LOT of noise...my 16.5" 308 HB that handles nice but because of the loss in velocity it doesn't even equal my 24" 300 Savage.

Asways choices to make.

Luck

[petemi]

Great job Pete... the numbers for the 38 are pretty surprising from the short tube.
A little off topic but do you think the same trend would occur with a short 44 mag? I've been thinkin' of givin' mine the chop.
Oh and good job not shootin' the chrony.



Spanky

I don't think you'd be missing a heck of a lot.  I suppose it depends what you want the rifle to do.  If you want to shoot deer under 100 yards, I don't think it'd make a difference.  If you reload, which you do, you can jack up the load over factory to make up for the shorter barrel.  I'd just go ahead and do it.  The shorties are neat.

Pete

[dpe.ahoy]

Thanks for posting this Pete.  The velocity swings aren't that bad compaired to some factory ammo.  The velocity loss for the max is pretty good for 5.5 inches.  I thought it would be more than that.  Gald to hear you missed the chrony.   DP