Printable View
So I dropped some of these bullets in water to quench harden them (they're a normal hard ball antimonius lead), and I'm wondering what kind of powder and charge weight to run under them to get them JUST UNDER super sonic. I wanna use them for hog head devastation, and want as much energy as I can get w/o a crack. This will be a load for a 16" carbine Winchester.
Thank ya!
I have always pushed them with 8 gr. of Unique. Been doing that for 40 years.
What kind of chonograph data did you get from that load? According to my load data book (lyman 49th) that load should be only coming out near 800fps....
What gun what barrel length?
Winchester 92 carbine levergun. 16" barrel length
I would probably start at about 17 grains of 2400, then adjust up or down to get the performance I am looking for. Standard primer.
ETA: This was before I saw you were looking for subsonic in a rifle. Ya' don't think that was pertinent enough to mention up front?
I looked back at my records... way back (1997) when I was doing quite a bit of experimenting with the .45 Colt in my Ruger Bisley 7½ inch. Mostly I was playing with the "slower" pistol powders trying to develop a load with respectable velocity without pushing the pressure limits.
Using a 260 grain cast boolit, 20.0 grains of IMR 4227 produced 980 FPS, 22.5 grains produced 1085 FPS. A 16 inch rifle barrel should add appreciable velocity to the load... meaning the 22.5 grain load would likely be supersonic, but something around 20.0 - 21.0 should get you what you're looking for.
A few notes...
Pressures seemed to be well below limits as cases fell from the chambers under their own weight.
Ballistic uniformity would run excellent for 8 or 10 rounds, and then an occasional "slow" round would drive the extreme spread up to 100 FPS or so for a 24 shot string. I tried a magnum primer thinking the problem might be ignition... it helped, some, bringing the ES down around 70 FPS.
The ballistics matched the target... most shots clustered in a very impressive tight group, but there was always those pesky 2 or 3 fliers.
Anyway, I gave up on IMR 4227 believing the cylinder gap and (relatively) short barrel was not allowing the propellent to burn completely/efficiently... but your 16 inch (gapless) barrel may be just what the load needed to straighten out and start driving tacks.
*
No magic answer as it all depends on a lot of factors you can control and many you can't as to what velocity the "crack" will start. Also the less powder used the total gas volume and heat the suppressor has to deal with. I suggest Unique powder.
I suggest you simply start with 7.5 gr Unique under that bullet and work up in .2 gr increments. W/o ear muffs on shoot at least 3 but preferably 5 shots of each increment listening for the "crack". Best to have an assistant off to the side of you 5 - 10 feet listening also. At the first "crack", not multiples of "cracks" but the very first "crack" back off to the last increment and that is what you want for the conditions (ambient temp, humidity and barometric pressure) you tested under. Backing of 2 increments (.4 gr) will be a pretty good bet unless there is a radical change in conditions.
Once you've done all that then test position powder to rear of case (muzzle up, gently lower to fire) to see if it "cracks". Same with powder position forward (muzzle down, gently raise to fire). If no "cracks" your good to go.
Larry Gibson
Would it be a good idea to use a wadding to get consistent powder location in the case for this type of control?
Also, I would think that if I aim for a flat 1000fps (since the speed of sound is around 1115fps on a "normal" day), I should be pretty safe. I have a chronograph (competition products prochrono) so I can validate velocity that way.
My 7-1/2" barreled new vaquero will push a 255 ish boolit to just under 1000 fps with anywhere from 8 to 9 gr of unique. Depending on the style and how far it sets inside the case.
For me a field pistol must be shootable without earplugs. Unique is usually my best performer with the most velocity versus decibels.
I suspect with a 16" barrel 8 gr will be plenty if not too much.
Why does hodgdon cartridge loads have .357 rifle data but not .45 colt? :(
Well, brought out my lyman on a hunch and they have rifle data for a 16" barrel. Best group with 255 SWC's was with 6.2 grs of titegroup over a winchester large pistol primer, rocking 1009 fps. Seems like a winner winner chicken dinner to me!
I need a 45Colt lever gun........
Not with a suppressor.........Quote:
Originally Posted by Boosted98gsx
Larry Gibson
True enough.Quote:
Originally Posted by Larry Gibson