45 Colt velocity increase in a rifle

[reloaderman1]

I need a little help. I loaded my 45 Colt ammo to pistol specs, and I'm wondering what kind of increase will I get shooting out of a 20 inch barreled rifle?
I used to have a crony, but............ it's only a matter of time before I had to shoot it! It took offense at a .243 load I was testing and charged, luckily ,I was able to drop it just 15 feet from the bench.

[felix]

You can count on no more than 200 fps. ... felix

[paul h]

There are a whole bunch of caveats that can throw speeds one way or another, but I'd expect a 20" rifle to be 300 fps faster than a 7 1/2" revolver.

As a rule of thumb I figure when you go from a revolver to a closed breech, expect a gain of 100 fps, and expect 25 fps velocity gain for each additional inch of barrel. That would add up to closer to 400 fps, but pistol rounds, especially lower intensity ones, tend to not quite follow that rule to a T.

[Trey45]

Agree with Felix, 200fps gain at the most.

[Doughty]

Reloaderman,
As with most things cast, "it all depends." My .45 Colt load in a Ruger 4 5/8 barrel, with Rex II and a 280 grain boolit gives velocities in the high 800s. The same load in my switch barreled Marlin 94 with the 16" barrel shoots in the low 1100s. With the 24" barrel the velocity is only in the high 1100s. If I go with a hotter load using AA#7, the pistol goes to the low 900s, the 16" to the 1200s and the 24" to over 1500. I think if you went with hot loads of AA#9, H110, Win 296, or AA1680, the spread would change again. Throw in a 7 1/2" pistol and they would change again. .45 Colt is a pretty versatile cartridge which you can make of it what you want.

[jmort]

More than 200 fps is common. Here are some "real world" numbers, 400 fps plus difference.
http://ballisticsbytheinch.com/45colt.html

Cor Bon 225 DPX +P
Cimarron Colt 5.5" barrel 1087 fps
1892 Winchester (repro) 20" barrel 1599 fps

[missionary5155]

Greetings
I would also add depends on your "pistol" specs. Huge difference in strength between a Colt New Service 45 Colt to a Dan Wesson 45 Colt. I can load safe cartridges in the DW that would possibly open the cylinder on the Colt New Service.
A load powered by Unique will do little better in a 20 inch barrel. But try 296 or 1680 with a heavy boolit and you will see some good gain.
Mike in Peru

[runfiverun]

your average 14-k pressure load swapped over to a rifle will only have about a 150 fps gain.

throwing a slower powder in the mix that generates much more gas volume will show a better velocity increase, of course the pressure will be higher also and will destroy many 45 colt revolvers. [and be nowhere near max pressure in others]
the question becomes a bit subjective.

[Harter66]

Its not a 45 but .........
My 18'' Marlin gave 200fps more than the 6'' Sec 6,in both 357 and 38s w/Unique.

[jmort]

"your average 14-k pressure load swapped over to a rifle will only have about a 150 fps gain."

Not exactly, more like 300 plus fps, about twice that

Federal 225 gr. semi-wadcutter Lead HP

Cimarron Colt 5.5" barrel 791 fps
1892 Winchester (repro) 20" barrel 1122 fps

http://ballisticsbytheinch.com/45colt.html

[JeffinNZ]

Will depend greatly on the powder you loaded. A very fast powder will add less velocity than a slow grade.

[reloaderman1]

Thanks guys, I was thinking about 200fps, I'm glad it could be more. Hey, it shoots great without knowing!


Thanks again

[Outpost75]

Velocity Vs. Barrel Length - .45 Colt, Saeco #955, 260-gr. FN, 10 BHN, LOADED UNSIZED .455” LLA
Starline brass, 1.285” case length, WLP primer, Alliant Bullseye, Ctg. OAL 1.59”

LD______Grs.______Colt______Ruger______H&R________ Average of five consecutive
Rotor____BE______5-1/2”____4-5/8”_______20”________Five-shot groups
#9______5.0____685,24Sd___704,24Sd___878,32Sd_____ 2.73” from H&R CR45LC carbine at 50 yds.
#11_____6.0____807,28Sd___809,27Sd___1027,18Sd____ 2.99” H&R carbine at 50 yds.
________________________________________________2. 63” Colt revolver at 25 yds.
________________________________________________2. 96” Ruger revolver at 25 yds.
#12_____6.5____900,18Sd___914,14Sd___1093,7Sd____ 2.08” H&R carbine at 50 yds.
________________________________________________2. 39” Colt revolver at 25 yds.
________________________________________________2. 69” Ruger revolver at 25 yds.

Ruger shot best when bullets were sized to .452", but groups with Colt with sized bullets enlarged to 4"+ with keyholing. Cylinder gap of Ruger NMB is 0.005" whereas Colt M1909 is 0.008". Throats of H&R CR45LC are .457" and larger bullets, if available would probably shoot better.

 

[garym1a2]

With W296 or IMR4227 or similar I would expect a good bit more than a fast powder like Bullseye.
With my 357 Rossi I got a very large increase when using a stiff charge of 2400.

[superc]

I did some loads out of Elmer Keith, except with Hornady 250 gr. JHP (XTP) bullets.

From a 4" revolver I got about 1100 fps. See my video of the test at https://www.youtube.com/watch?v=3aUSZiIQU1Q

I then fired some of the same load through a Winchester Trapper Carbine. This produced velocities of about 1600 fps. The video of this test is at https://www.youtube.com/watch?v=BHc0Wl5yFVw

It is probable the powder charge used is maybe a little stiffer than what is written in the video and more in line with what E. Keith used to blow up his sixguns.

My point is, I got a 500 fps jump when going from 4" to 16".

[Tackleberry41]

I have found its about 200fps from a pistol to a rifle. But depends on the powder, cowboy loads, stays about 200fps. Slower magnum powders will really speed them up in a long barrel.