Chronographing Loads - Which Barrel Length?

[101VooDoo]

I'm getting ready to make a trip to the range next week to chronograph some .44 Special loads, and it occurred to me that I've got .44 Specials with 4 5/8 and 5 1/2 bbls, and .44 Magnums with 6 1/2 and 7 1/2 bbls. :?

Just out of curiosity, when you chronograph loads for calibers that you have in multiple barrel lengths, what would you pick and why?

[Larry Gibson]

Why "pick" one barrel and then guess the velocity from the others? Why not just chrono the same loads from all the barrel lengths you have?

Larry Gibson

[rnelson11]

Why "pick" one barrel and then guess the velocity from the others? Why not just chrono the same loads from all the barrel lengths you have?

Larry Gibson

I agree. You can get good results from about 10 rounds (avg & st de). That would only be 40 rounds total.

[btroj]

I only have a couple of situations like you mention. In those cases I do like Larry said and chrono them all. The velocities in each will be different so why wouldn't you do this? I want to know wha the velocity is for that particular load/ gun combo. The velocity of the ammo doesn't matter without the context of the gun it is shot in.

[Maven]

101VooDoo, That's a difficult question to answer because it assumes velocity and bbl. length are directly and perfectly related. E.g., I have both4 5/8" Ruger BH and a Dan Wesson 6" .357mag. revolvers. When I chronographed the identical load in each, I was surprised to find that the shorter bbl. was significantly (i.e., not by chance) faster than the longer one. That result may have been due to differences in bbl. smoothness or cylinder gaps, or possibly would disappear entirely if I repeated the test say 50 times.

[subsonic]

Chrono in the gun you want to know velocity from, or whichever one is most pleasant to shoot.

[101VooDoo]

Why "pick" one barrel and then guess the velocity from the others? Why not just chrono the same loads from all the barrel lengths you have?

Larry Gibson

Larry - I had thought about that, but in this case I was going to test 3 different weights of Power Pistol, 3 of True Blue, and 7.5 grains of Universal, so it'd end up being around 280 rounds. Think that might be a bit impractical in this case, though the data would be interesting.

Maven - these are all Ruger Single actions, by bbl length they're: FT .44 Spec, Bisley .44 Spec, Anniv .44 Mag, and Vaquero .44 Mag. I'm thinking the barrel dimensions might be reasonably similar, though I understand that variations in cylinder dimensions, cylinder gap, forcing cone etc. will affect results.

[cajun shooter]

I can't understand the reason for the question in the since that you probably own all these guns and want results from what the forum decides. Why not pick your most favorite gun to shoot and that would keep others from having you test the gun you don't favor as much. Is there some sort of time problem that would keep your test limited? I would want every result that I planned on shooting and using. If you have no plans for a certain load then skip it and make your decision. That is the one that could have been the magic bullet. When you put a limit on any test you are trying to fail. It's the What If. I did not vote so that I would not be the entry that caused failure.

[Larry Gibson]

Larry - I had thought about that, but in this case I was going to test 3 different weights of Power Pistol, 3 of True Blue, and 7.5 grains of Universal, so it'd end up being around 280 rounds. Think that might be a bit impractical in this case, though the data would be interesting.......

I understand now; you are testing loads, not simply chronographing already developed loads. In that case I would select the particular revolver I shoot best. If not known then I opt for the longest barrel. Once a specific "load" with each powder is selected I would then test/chronograph it in all barrel lengths. That cuts down the total amount of testing.

The down side to that is that you are selecting a load which is "best" in one revolver and just accepting it in the others. That's what I do with multigun cartridges I use also. A lot easier logistically that way and I get very acceptable, to me, results that way.:D

Larry Gibson

[Matthew 25]

I'd like if you shot 2-3 revos and posted your data. I recently got the same velocities from a 4 5/8 RBH and a 7 1/2 RBH --two different loads did this. I only shot 5 shot groups over the chronograph, but I intend to repeat the day with more rounds.

[101VooDoo]

Larry - not sure which I shoot the best, I think I'll go with the Bisley, as it's got the longest barrel with a .44 Special cylinder. Once I get a load picked out I'll make some 'production' loads and try them in each.

Cajun - not time limited anymore as I retired in Jan, but in Nevada's high desert its usually 100% sun and hotter then hell by 11-12. So I can usually get about 3 hours or so in before then. Not really looking for decision by forum, just figured I wasn't the only one that had come up against the problem. I guess I really shouldn't consider having so many .44s a problem... :happy dance:

Matthew - will do. I've taken to loading 12 of each for testing, seems if I only load 10 I'll get one or two that won't register.

[btroj]

Larry was dead on. Use the fun you shoot, or feel most comfortable with, and use it. Find a good load for that gun and then see if the others shoot it well enough too.

Nothing worse than having different loads in one cartridge for different guns. A logistical nightmare to me.

[HammerMTB]

I test in every gun I own and want to know the results.
The results don't always follow the norms "assumed" by the magazine writers and those who purport to know about such things. My Glock 20 and 29 give almost identical results despite ~1.5" bbl length difference.
I do think you will find a pattern develop using your own guns that in time will become predictable enough that you won't "have to" test every combination.
To me, finding out the facts is interesting enough to make the shooting and recording another part of the fun.

[subsonic]

Speaking of weird stuff, I have swapped a 2.5" 686 .357 back and forth with a buddy of mine whenever we get tired of it. It is faster than 2 other 4" .357's and almost as fast as my 6" 686 with a certain load -> 17gr of AA9, CCI550 and a 125XTP = 1500fps from this nasty little gun.

[white eagle]

being that each gun is its own identity
I do crono them separately
all mine wear 5.5" barrels ana way
just sayin

[stubshaft]

Chrono in the gun you want to know velocity from, or whichever one is most pleasant to shoot.

Totally agree.