Barrel length question

[Stacts]

I recently finished reading 6 Guns by Elmer Keith and I was hoping someone on here could answer some questions I have.

Keith implies that a 4" barrel SA in .45 Colt was a short barrel in the 1800s and that 6" or 7" were common. Nowadays, a 4" handgun is considered big and there are very few with barrels as long as 6". With modern (smokeless) powders, a 4" barrel is plenty to get full burn (excepting certain magnum powders).

Does black powder burn slow enough that barrels exceeding 4" provided additional velocity? What kind of velocity gain should one expect? What variety of BP was typical of .45 Colt?

[gunther]

A 7 1/2 inch Old Army loaded with 43 grains of 3f and a 45468 hollow base 180 grain bullet will get you 1050fps. Never chronographed a 5 1/2 inch one to compare, but there's gonna be a difference. Maybe someone else on this site can chime in with that information.
Smokeless loads in modern revolvers lose about 30 fps per inch removed from the barrel. That's pretty well documented.

[country gent]

Barrel length isnt always or just about velocity. Sight radius on a longer barrel improves shoot-ability, The longer barrels may balance better than shorter, And in Keiths day handguns were shot fast normally by instinct and a longer barrel may point better.

[Thumbcocker]

Then there is barrel cylinder gap. Also, I know some older shooters who prefer 4 5/8" barrels. They say that they get a clearer sight picture with the shorter barrels.

[HWooldridge]

Longer barrels on the early revolvers would have been better with black powder. Same reason many rifle barrels were longer than what we typically see today.

I have all three standard Colt barrel lengths. The 4-3/4" is the handiest and plenty accurate at most ranges. The 7-1/2" holds better for deliberate target shooting but is harder to lug around on a belt. Personally, I never saw much use in the 5-1/2" version - it's a compromise that misses both of the other lengths, but some people love it. My son has a 5-1/2" .45 Colt and thinks it's the best size ever invented. To each his own...

[Stacts]

Longer barrels on the early revolvers would have been better with black powder.

That's my thinking. I just wanted to know some numbers.

[Froogal]

I get better accuracy with my 7 1/2" barrel than I do with an identical gun but with the 5 1/2" barrel. Probably is just me.

[Mal Paso]

If you are talking about full power 44 Mag, 6" has much less muzzle flip than a 4" and 50-100 more fps. Guys with 2 inch barrels are suddenly talking reduced loads even though the Muzzle Energy is less.

I shot the 6" Anaconda today. 20g of 2400 under a #503 for about 1350 fps. I was still fresh after 126 rounds, the 4" gun, I would have stopped at 50. Problem is my muscle tone is down and I need to stand there and practice, the reason I replaced the 6 inch.

Best part, these were 15 cent a piece rounds from old stock.

[Stacts]

Where did I mention .44 Mag? Could have sworn I was talking about black powder loadings of .45 Colt.

[M-Tecs]

And in Keiths day handguns were shot fast normally by instinct and a longer barrel may point better.

Elmer Keith was born in 1899 and he was very fond of good sights on his handguns. Even his fixed sight 1873's had custom fronts and rears added. In the 70's I modeled my long-range revolver shooting after Keiths methods. They were based on using the sights.

Some good pics here

https://americanhandgunner.com/disco...shots%20rifles.

https://www.rockislandauction.com/de...arget-revolver

https://bulletin.accurateshooter.com...million-worth/

https://gundigest.com/more/classic-g...of-elmer-keith

https://www.bing.com/images/search?q...mageHoverTitle

https://www.fieldandstream.com/guns/...lver-for-sale/

https://elmerkeithwasdeadright.blogs...-who-ever.html

Long-range handgun shooting is done from all the conventional positions, such as prone and offhand, and includes an Elmer Keith innovation called the sitting back rest, where you sit on the ground with your back braced against a tree or other vertical backing and your knees are raised to provide support for your arms while shooting. Keith also gives some unconventional advice on long-range sighting with factory iron sights. The problem is, if you just raise a conventional sight picture higher than you want to hit, you obscure the target, and aiming somewhere in the sky above your target can hardly be considered precise gunhandling. The Keith method is to hold the front sight blade up above the rear notch a certain measure. It takes a while to determine how far to raise the front sight for different ranges, but the technique can be surprisingly accurate out to about 500 yards.

[Milky Duck]

Where did I mention .44 Mag? Could have sworn I was talking about black powder loadings of .45 Colt.

ouch.....


in similar vein...you asked what variety of black powder would have been used in .45 colt....
well I will asume you are meaning the .45 long colt...and not a .45 cap n ball or short colt or std colt
and will answer your question directly and accurately..... it would have been loaded with the type of powder the person reloading had at hand.....
now before you get all hot under the collar..
from what ive read,during your fellas wee civil unrest a few years ago...the Southern fella were making black powder using cotton woods/poplar...rather than the more common crack willow...... so the powder on hand could be of many and varied sources..... some would be best swiss imported stuff...other stuff home brewed other stuff commercially made from many factories both sides of the mason dixie line
in short,black smelly stuff is black smelly stuff..the granual size may be different and a particular size eg FFF might have been the flavour of the month...but the weight of charge would probably have been very similar across the board.
a longer barrel gives powder longer to burn....30" rifle or shotgun barrels were common for that reason....
so yes a longer barrel would give higher velocity and a better sight radius...that hasnt changed over the years.

[Stacts]

ouch.....


in similar vein...you asked what variety of black powder would have been used in .45 colt....
well I will asume you are meaning the .45 long colt...and not a .45 cap n ball or short colt or std colt
and will answer your question directly and accurately..... it would have been loaded with the type of powder the person reloading had at hand.....
now before you get all hot under the collar..
from what ive read,during your fellas wee civil unrest a few years ago...the Southern fella were making black powder using cotton woods/poplar...rather than the more common crack willow...... so the powder on hand could be of many and varied sources..... some would be best swiss imported stuff...other stuff home brewed other stuff commercially made from many factories both sides of the mason dixie line
in short,black smelly stuff is black smelly stuff..the granual size may be different and a particular size eg FFF might have been the flavour of the month...but the weight of charge would probably have been very similar across the board.
a longer barrel gives powder longer to burn....30" rifle or shotgun barrels were common for that reason....
so yes a longer barrel would give higher velocity and a better sight radius...that hasnt changed over the years.

Thanks. I know practically nothing about BP which is why I was asking.

My Hornady 11th used a 3" .44 spcl (using .44 spcl because they both use 7" barrels for .45 Colt), but Hodgdon used an 8" .44. When comparing their data for a 240 gr cast lead and HS-6, Hornady gives a velocity of 750 (8.1 gr) while Hogdon gives 917 (8.0). Admittedly not apples to apples, but that seems like very little gain for 5 inches of barrel. I was just wondering if BP behaved differently.

[Milky Duck]

917-750=167 that is A LOT of gain... 25% increase in velocity is a lot of increase in terminal power no matter how you look at it.... hunters have known for years that the best loads are ones that shoot accurately enough to hit where you aim with as much velocity as you can get..within reason... no point in being silly about it.
to put that 25% increase into perspective.... its 30/30 VS .30-06 or .222 Vs 22-250

[Kosh75287]

ANOTHER major factor (or two) in determining the gain/loss of velocity in cartridges as a function barrel length is not only functional chamber pressure, but the ratio of case capacity to bore diameter. If you fire and chronograph factory .45 ACP rounds from a 4" barrel and a 6" or 7" barrel (all other factors being equal), you'll likely notice a definite if negligible increase in muzzle velocity. As stated somewhere above, if the same is done with a .45 Colt, a more noticeable increase in velocity will likely be observed, but the difference is partially obscured by the fact that the .45 Colt operates at ~2/3 to 3/4 the chamber pressure of the .45 ACP. Were the .45 Colt loaded to the same chamber pressures as the .45 ACP and fired from 4", 6" and/or 7", the velocity differences would be far greater, and probably useful.
In rifles, the .243 Win., .308 Win. and the .358 Win. have essentially the same capacities and operate at essentially the same chamber pressures. If you start with 26" barreled rifles in each caliber, chronograph the velocities of each, remove 1" of barrel length from each barrel and re-chronograph, you'll notice that the velocity drop after each barrel shortening will be greater for the .243 (actual f/s), followed by the .308, and less than either for the .358. This tends to explain why .357s are semi-awesome with 6" or longer barrels, and tend to be more like an angry .38 Spl. +P in 2.5" and shorter barrels.

[LeonardC]

Once upon a time: I did a test for myself using a Dan Wesson .357. I had barrels & shrouds in 4", 6", and 8". I did OK with the 4", a LOT better with the 6" in place of the 4", and only improved about 10% less group size when I went from 6" to 8". I also had a DW .22 and had the much the same results as the .357.

The first handgun I shot was my Dad's K22 with a 6" barrel. I still like shooting the 6" guns better than the others. 4" carries easier, the 7.5 and 8" barrels if top accuracy is required.

[Harter66]

Practical application but not wholly applicable.
Per the Lyman 48th and forward the only difference between a max load at Trapdoor levels in a 45-110-405 and a 405 in a 458 WM start load is 10" of barrel .

From the available 38 and 357 4&6" barrels to an 18" 1894C there was a gain regardless of loads chosen of 375-425 fps . I used to just call it 400 fps but some snarky over full type called me out about the impossibility so I'm more specific now . Or something.

Moving to 45 Colts I get 200 fps MV from a 7.5 RBH to a 16" M92' and no additional gain for going to the 20" with Unique and 545424 257 gr Lyman, 454-250 NOE version, and the 452-255 RNFP Lee @265 gr . I don't have a direct comparison as for whatever reason I just haven't chronographed the "hot loaded" 45 S&W in the 7.5" barrel , it's pretty sassy at 250 gr and 900 fps from a 3.5" barrel .

In as close to what you're actually asking as I can get I shoot own self screened BP in a common 7.5" brass 1858 reproduction. By volume loose dumped full cylinder , so like 40 gr , I get 750 fps with a 141 gr cast ball . If I tamp it down and fill it again , loose measure now approaching 55 gr and seat the ball I get nearly 800 fps MV. When I use 30 gr of Goex FFg by volume it gives me 825 fps MV.
When I used T7 at the same volume I had 910 fps vs 875 fps for FFFg Goex .

The burn rates of BP is determined by exposed surface area the same charge by volume of FFg will have only about 1/2 of the exposed area of FFFg so it burns slower at lower pressure. Sort of , it actually just takes longer to reach it's peak pressure which is about the same .

T7 , pyrodex etc , subs are as I understand it using basically sugar in place of the charcoal because a chemist says carbon is carbon here . The same rule applies here more or less .

The only real way to know would be to have a switch barrel revolver with identical cylinder gap and several barrels cut from a single barrel blank and one set of finish tools and shoot them on one frame and cylinder at 3,4,5,6,7" lengths. Aside from the butt stock there had to be some useful gain or the Buntline Special wouldn't have been a thing.

I suppose you could get an 1860 style cattleman's carbine barrel and a conversion cylinder or even one of the 12" target models of the 1858 and cut it back from 12" and see what happens.

[charlie b]

This is when I wish I had used my chronograph more in the old days. I had a Remington (7 1/2 barrel) and cut it to ~4 1/2 (shortened ram and reshaped grip to bird's head, nice handling 'little' gun). Never recorded any velocities after I cut it....dumb. A friend used it as a belly gun in SASS to go with his Remington in the holster. They looked good together.

[Jtarm]

Not really related, but the market duck hunters of old worked up BP loads for their “big guns” by firing with the barrel parallel to snow-covered ground. They kept increasing the charge until un-burned powder appeared on the snow.

I’m sure the 19th-Century Colt SAAs were most common with 7 1/2” barrels because that’s what the Army issued. 4 3/4 and 5 1/2” barrels probably seemed short by comparison.

IDK if powder-burn efficiencies factored into the 7 1/2” barrel. More likely it was the approximate length of most percussion revolvers issued to troops, especially mounted troops for whom barrel length may have been less of an issue than a ground-pounder.

Although hailed as a man-stopper, Army sidearms of the era were intended to be horse-stoppers as well, since the best way to deal with a mounted enemy was to shoot his horse.

[Stacts]

That is fascinating.

[Ed K]

A little off-topic but a good resource for persons inquiring about this sort of thing:

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