Just got done running another (successful!) experiment with milsurp IMR 7383.
I've been told by the "experts" that 7383 is marginally safe in rifles and absolutely useless in pistols. I set out to find out for myself.
I chose a Ruger Vaquero in .45 Colt, large magnum pistol primers and 230 grain FMJ round nose bullets for the test. From my experience with 7383, I know that it starts peaking at about 95 to 100 percent load density in botlle neck rifle calibers. I started with 100 percent load density and went up 1/2 grain at a time.
I went through several grains of charge increase until I found the pressure signs I was looking for. I will NOT publish the charge weight, but I will tell you the final charge was very compressed. As a matter of fact, I got within 2 grains of the final charge before I found any pressure to speak of. The primers continued to stay rounded and the cases continued to come out sooty and smoked at the mouths and on the sides.
However, when the pressure did hit the sweet spot, the primers immediately flattened and the soot and smoked case walls went away.
Taking all this into account, it must be remembered that the test bullets were relatively light for the caliber. I feel certain a load can be found for bullets in the 250 grain range and I believe a load can be found for bullets as heavy as 300 grains.
I've been experimenting with and using 7383 for about 5 years now and I've learned that it CAN be used in a very wide range of calibers and bullets. One PRIMARY thing I've learned is this: Start at about 90 percent load density with standard primers and switch to magnum primers BEFORE you increase the charge. Increase the charge 1/2 grain at a time and TAKE YOUR TIME. This powder has a tendency to spike VERY quickly. I fire a round, extract the casing and look for pressure signs before I proceed with another round. If I find the sweet spot before I fire the entire batch of test loads, I take them back to the bench and pull them.
The horror stories you have read and heard are all true. However, they are a result of handloaders using flawed and/or foolish methods if any method was used at all. If a planned, scientific method is used, a load can be found using 7383. As inexpensive as this powder is, It would behoove the knowledgable handloader to investigate it.

Puncher

More data..........

In the coupla' hours since my first post, I worked up loads for two more bullets using 7383. The first was a 255 gr. flat point round nose cast in a Lee mold using alloyed lead. This bullet drops from the mold at about .455 and is sized to .454. The second bullet used was a 325 gr. FPRN(.45-70 bullet) and it drops at about .460 and is also sized to .454. Both bullets were lubed with Lee Lube. The alloy consisted of about 90 percent wheel weights, 9 percent tin and 1 percent copper(for hardening). These cast bullets were water cooled for extra hardening.
As with the 230 gr. FMJs, the charges were compressed and printed the primers, but did not cause riveting.
230 gr. bullets are a bit light for the .45 Colt caliber and 325 gr. bullets are a bit heavy. Having used bullets that weigh in at both extremes of the spectrum and one that's about average, I feel that I can use IMR 7383 successfully in the .45 Colt.
I very seriously doubt if I'll ever pay 20+$/lb. for canister powder again.

As an aside, I was able to recover one of the 325 gr. bullets. I had fired it into a dead hardwood blowdown about 5" in diameter. I noticed the dirt behind it kick up when I fired and I found the bullet imbedded in the ground. Except for minimal marring at the tip and rifling engraving, it was not deformed. I put it on the scale and found that it only lost 2 percent of the as-cast weight average. Don't know for sure, but I doubt that a 230 gr. FMJ could stand that without deformation. I like them hard cast bullets!

Puncher

Interesting posts. Just goes to show you that conventional wisdom has its limitations.

Did you check the velocities you were getting? and how was your accuracy?

These loads were not chronographed as I was only interested in pressure signs. 7383 is a pressure sensitive powder and I was trying to determine if I could use this powder and how much it would take to develop enough pressure to print the primers.
As for accuracy, The pistol is a Ruger Vaquero with a 4.5 inch gunfighter's barrel and fixed sights at that. All I did was walk down in a dry wash and fire the loads to check for pressure development.

Puncher

quote:

Originally posted by Puncher:
This powder has a tendency to spike VERY quickly.YOU got that right


The horror stories you have read and heard are all true. However, they are a result of handloaders using flawed and/or foolish methods if any method was used at all. Puncher

This is pure Puncher, you have been pushing IMR 7383 since the first time I saw the handle Puncher and HI TECH used in the same paragraph.Many of us have pointed out and shown that there are usable areas for 7383. We've also shown it is fool hardy to treat it like any other powder when trying to find maximum charges. Distorting the efforts that honest, safe reloaders contributed to try an unvail the danger zone this powder has is really sad for a professed member of the shooting Brotherhood.

I don't know what your conection is with those that are selling this powder, if any, but your postings sure are questionable. Why are you trying to push this stuff??? The only questionable methods I see in this thread is your propagation of what could prove to be a dangerous situation.

If any knowledgeable handloader wants to see the evaluation and report that many contributed to,intially including, Puncher, until he begged off because he didn't want to incurr any liability,[whatever he meant by that] I'll be glad to E-Mail it to them.