Velocity Loss From Standard 5" .45ACP To 3" Compact

[Landy]

What velocity loss have you seen between 5" and 3" .45ACPs with full but not +p 230 grain loads?

Does powder burn rate effect it? Ranch Dog lists some powders as burning fully in 2.5" and some in 5".

[shoot-n-lead]

We have chrono'd a good many, as we are 1911 fans and found that there is not a lot of velocity loss...or at least, not enough to stop us from carrying them.

[dubber123]

I read a test of 3,4, and 5" 1911's a while back. As I recall, the spread was less than 50 fps.

[Greg S]

828 avg on a 5 and 790s with a 3.5 if I recall correctly. Can't remember the load, factory or homebrew but most likely it was a 230 fmj load.

[bosterr]

I shoot a 200 grain #68 H&G style SWC in my 3" Kimber Ultra Eclipse and in my Kimber 5" Gold Match. Back when I was shooting 4.9 grains of Red Dot, the 3" gave me 820 fps with 43 extreme spread. The 5" gave me 922 fps with 43 extreme spread. I never tried 230 grain boolits and use Win. 231 now since I got a good deal on 5 pounds of it and meters better than Red Dot. Red Dot had the accuracy edge though.

[Landy]

Thanks, good info so far.

The economics and availability of the Vectan powders is calling, but I've found no TL452-230TC (Only 45 this new caster has so far) data.

I'd match burn rates and match chronograph averages with a ladder of loads, but all the data is for 5" and all of mine are 3" guns.

[Boogieman]

My 3.6" Colt O.M. looses about 75 fps from my 5" Colt. This holds true with every load I've tried.
Type of powder didn't change much, used B.Eye, titegroup, and BE86.

[Outpost75]

I haven't done side-by-side comparisons with short and standard length 1911 platforms, but have compared an ordinary GI M1911A1 pistol to revolvers of various lengths:

Ammunition__________S&W 625 3"______Ruger BH 4-5/8"____M1911A1 5"_____S&W M1917 5-1/2"
____________________cyl. gap .006_____cyl gap .005________solid bbl________cyl. gap .008

FC61 Ball____________778, 9 Sd________820, 9 Sd__________862, 4 Sd_______837, 13 Sd

Speer 230GD ShtBbl___764, 22 Sd_______800, 14 Sd_________844, 4 Sd_______845, 10 Sd

Win. 230 SXT_________757, 12 Sd_______803, 5 Sd_________858, 8 Sd_______ 851, 16 Sd

[jcren]

Look at ballisticsbytheinch.com for some interesting data on various factory loads in tc barrels cut down an inch at a time.

[Groo]

The loss of the 3in over the 5 [or even the commander]
is why I tend to use Hardball in the short barrel.
Ideal would be a flat nose,or if CCI would bring it back out , the 200gr SWC TMJ Combat Match.

[Artful]

Look at ballisticsbytheinch.com for some interesting data on various factory loads in tc barrels cut down an inch at a time.

Best reply so far
http://www.ballisticsbytheinch.com/45auto.html

[Yodogsandman]

Here's a comparison in castpics...

http://www.castpics.net/LoadData/Sur...s/45acp_BD.htm

[Landy]

Thanks all.

This in composite indicates 3" barrels achieving 90% of 5" specs in standard ball and target loads and 87% in hotter SD loads. This gives me something to work from.

Groo, you've a good point. At these velocities (and likely even some higher) a big solid flat point is likely better and more reliable than expanding designs.