View Full Version : .44magnum and the marlin 1894
09-05-2011, 05:33 PM
Was using the following load today.
A montana bullets 240 grain S.W.C. gas checked with a heat treated bullet of lyman No 2 to a BHN hardness of 22. This is a N.E.I. mould.
They WERE SIZED to .432 and lubed with LBT Blue lube
Powder was AA no 9 which per the online accurate guide showed a minimum of 18.1 to 20.2 max and I used 19.8. I later verified this by pulling a loaded round and i got 19.8 grains.
I wanted to use the .432 diameter bullet, although .44magnum is nominally .429diameter in a marlin 1894 lever action which had a slugged bore diameter of .4315 which is common for these rifles.
The accurate loading site showed with minimum load of 18.1 using a 8.25 inch barrel velocity of 1255, and with the max load of 20.2 a velocity of 14225fps.
Given the 20inch barrel on the marlin rifle, the following wasn't too surprising:
given the barrel was 12inches longer than the accurate 8.24 test barrel, this would be about in line.
I THEN PROCEDED to fire the same rounds in a S&W model 29 4inch. I had previously measured the barrel diameter in this pistol at .429
This was in hindsight a mistake, although i had received a lot of comments that .3000 over in lead wouldn't mean much. It didn't mean much in that the pistol didn't blow up, and i see no obvious signs of cracks. But this is what the chrony showed with the same bullet until i stopped.
Interesting enough i got no sticky extraction or other signs on the casings. But aint gonna do it again.
The only thing i can think of is that three thousandth's over was the culprit.
Welcome to the wonderful world of rifles and pistols chambered for the same rounds...I've been doing this for more than 40 years. I'm running .432 and .433 in 20 plus RUGER and SMITH&WESSON revolvers and 4 MARLIN rifles I have access to/cast for currently. (I have a bunch of step sons and their kids PLUS my own 48+ rounds per day for CAS practice.)
You've probably been around long enough to read through various thoughts on alloy hardness with a gas check boolit. Glenn Fryxell's article on 1894 MARLINS over at lasc.us is required reading...the others will add to one's education and save a lot of wasted components.
Other than being inclined to stay with the starting load of 18 grains of AA#9, if the accuracy is acceptable WITH no signs of over pressure, who would argue with success. One trick is to measure the sized casing with a micrometer and then again after you fire it...besides the usually mentioned hard extraction and flattened primers. It's also important to remember that a SMITH & WESSON will last a lot longer with lower end loads...even the newer ones with the 'ENDURANCE PACKAGE."
Not to offend, but I think I'd check the calibration on the chrony...either set of numbers for a 4 inch gun sounds extremely high.
09-05-2011, 08:25 PM
Where did you get your loading data? Your rifle speeds are about what I get with top loads of H110 out of a rifle. If you are getting faster speeds out of a pistol, then I'll assume that your powder is probably faster than H110, which scares me a little. I don't have my loading books in front of me now, or I'd look it up myself, but your data sounds warm enough to warrant double checking it against a second source.
09-05-2011, 08:30 PM
Back in the 70s and 80s, we routinely shot with boolits which were .002" over-sized, as that was the standard practice back then in my area (way before the internet and sharing information as widely/easily as these days). Of course, we didn't have chronos back then either... BUT, there wasn't any sign of 700fps extra velocity out of our pistols with .002" bigger boolits either.
I can't imagine the hardness or size being sufficient to up the pressure that much to get those kinds of readings from that short of a barrel...
My routine heavy load is 270gr Hvy. Keith SWC (my group buy) with 18.5grs of AA#9, and in the longest-barrelled 44 Mag. pistol I own (6.5"), I don't get much past 1300 fps with this load. My 5" runs right around 1200 fps with it.
I'd be inclined to agree with EDK. I'm betting that short barrel, or maybe the barrel-cylinder gap is causing bad readings with your chrono. I'd try re-shooting with a blast shield between the muzzle and the start screen. I had this happen the first time I set up my chrono, because I was too close, but having a shorter barrel (more gas being burned out in the atmosphere) could cause a similar effect.
09-06-2011, 07:17 AM
I've had bright muzzle flash from some warm .357 loads cause bad chrony readings in the past too. If you are getting a big bright muzzle flash, then you might need to move your chrony back another 6 or 8 feet.
JIMinPHX has the right idea. Move your chronograph farther away from your barrel. This helped me when I got erroneous readings outta my old Oehler 33.
09-06-2011, 07:21 PM
I totally agree with the above posters on the distance to the Chrony. You are getting phony readings for the pistol, and there really can't be much speculation here as I doubt you would still have hands if that pistol was actually generating 1900+fps. Even if the gun had lived thru it you would have had a very convincing evidence of a killer load, just by the recoil.
Put it like this ,,,, there would have only been one reading that day for the pistol :Fire: There also might be more convincing evidence in the form of a big divot between your eyes where the front sight hit you.
The pistol readings you are getting are not from the bullet they are from the muzzle blast.
You can expect 400-700 fps difference between a pistol and a rifle with the .44. but not the other way around.
I have never heard of, nor read about any .44 mag pistol pushing any size bullet above 1500-1600 fps and 1300-1400 fps is more like the normally accepted top end.
Any time you get bogus readings you should always question the set up. Not to say you shouldn't question your ammo too, but with the rifle as a base line, the pistol readings have to be suspect. Same ammo. They should have been around 1200-1300fps. So higher than the rifle immediately signals a big? Why?
Me and my Bro in law both bought Chrony's at the SHOT Show. Mine works perfectly, his says 2200 fps from his 3" barreled Kimber .45 auto.
Since there is no possible way you could shoot anything from a 1911 at 2200 fps we know the readings are bogus.
His .308 rifle with a 20" barrel and 150 gr bullets consistantly reads at @2700 fps which is right where it should be. Both guns shot thru the same Chrony set up.
I think it's pretty much accepted that the blast from a pistol barrel will over take the bullet as soon as it leaves the barrel. There is alot of unused energy in pistol cartridges and none of them are as efficient as any rifle cartridge, so alot gets wasted .
I think the whole key here is to talk to the Chrony people and find out how to get it to work right with the pistol rounds. Probably just a set up issue.
09-06-2011, 08:07 PM
I have used a Chrony for many years and the muzzle blast can affect the readings. What also can affect the readings is the sun, even with the disfussers in place. I shoot early mornings mostly and if the sun hits the Chrony from the side just right the reading are way off.
I have also used #9 and even now that Western has reviewed all the loading data I think the loads with #9 are on the hot side. Their start load is were I stopped when testing loads.
It is always good practice to load at the start loads and proceed in increments up from there.
Load data has been known to be off even from credible sources.
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