454424 over 8.2gr of Power Pistol in .45 Colt

[Silver Jack Hammer]

Finally got ahold of a 454424 and have chronographed it with Power Pistol. 8.0 gr gave an average of 834 fps, 8.2 gr gave an average of 820 fps. Why did .2 gr give a slightly higher measured velocity? Couple things. One I only chronographed 5 shots from each of the two loads. More test data would likely even out the numbers. Another possibility is that Power Pistol is a high pressure powder designed for the 9mm and 40. In the .45 Colt the burn is less efficient. The lower powder charge the less efficient the burn and the more extreme the velocity spread.

These boolits were cast with scrap wheel weight alloy on Friday, I was making a huge quantity of cowboy boolits with two 4 cavity molds at the time and cast a few 454424's. The 454424 were sized .454" and lubed with Alox, primed with CCI300's, brass brands varied.

Then Sunday I made a bunch of 454424's with an alloy of 6 parts wheel weights 4 parts Linotype Last night I was sizing and lubing them and my Lyman 450 handle broke. Fortunately I have two Lyman 450's so after scavenging parts I'll be able to size and lube these 454424's for shooting Friday.

[rintinglen]

That sort of thing happens all the time in small samples.
I don't know what your standard deviations were, but unless they were very small (Like single digit), it is very common for samples to overlap, especially when the increment of increase is so small (<2.4%). Most likely, the higher load sample just happened to measure on the low end of its SD, while the lighter load measured on the high end of it's SD.
IIRC, you need a sample size of at least 30 to really trust the information from a test sample.

[leftiye]

Put .2 more in maybe and see waht happens. Could be kicking it out out of the crimp (semi squib load/bipolar pressure curve) with one of these loads too. Try some dacron filler. If you're not invested (just gotta use this powder) in this load, these are anemic .45 Colt loads and a bulkier, slower powder (maybe blue dot?) might be an easier fix.

[Silver Jack Hammer]

I've got all kinds of data on different powders in the .45 Colt, Power Pistol was actually on the shelf at a local gunshop and Brian Pearce of Handloader magazine has mentioned 8.2 gr of Power Pistol in the .45 Colt lately in a couple articles so I thought I'd try it.

I've loaded up some 8.5 and 9.0 gr of Power Pistol to try. Funny thing is I'm getting higher velocities with the same load in my Ruger BH and better accuracy. 8.2 gr Power Pistol Ruger BH; 820 fps. 8.2 gr Power Pistol Colt SAA; 766 fps. The Ruger groups dead center and the Colt hits 6 o'clock.

It's the new 454424 boolit mold I'm looking to get a good load for. Yesterday I loaded up 15 gr of 2400 and 6.8 gr of Bullseye with boolits from my new mold, maybe I should try some Blue Dot too. As I peruse my notes I see 12.0 gr of Blue Dot gives me 858 fps with a 250 gr boolit in a Ruger. This 454424 drops slugs at 255 gr 458". It seems to clock a little slower than my 454190 when pushed with the same powder charge. I see the 454424 seats not as deep so there is a marginally more case capacity than the 454190.

2400 hits the target higher than Unique with the 454190 in the Colt and I'm needing to bring my groups up, both in elevation and velocity so I'm looking forward to see the next range results. Thanks for your advice, I'll try the Blue Dot.

[Silver Jack Hammer]

I was about to give up on my new 454424 because 8.5 gr of Power Pistol hit at 6 o'clock and only sashayed along at 784 fps. The extreme spread in velocities was 61 fps. Then 9.0 gr of Power Pistol hit 850 fps and the point of impact was immediately below the point of aim. Amazing how a half grain of powder increase brought the point of impact up to just about center on the target. This combination is worthy of some 30 or 50 rounds to experiment with. 9.5 gr of Power Pistol might be where I end up at.

Also I've got some more work to do with Blue Dot.

The Colt's with the fixed sights make getting a load to zero, group and hit hard with different powders and boolits a challenge.

[Love Life]

I have bad news for you. Your SAA is broke. It can't be fixed. You can send it to me and I will dispose of it properly...

[Larry Gibson]

Finally got ahold of a 454424 and have chronographed it with Power Pistol. 8.0 gr gave an average of 834 fps, 8.2 gr gave an average of 820 fps. Why did .2 gr give a slightly higher measured velocity?

Reason #1; insufficient sample size. There is a reason the industry standard for testing ammunition is 10 shot test strings. For statisical validy (assurance) a 7 shot test string is the minimum. Even then a 10 shot test string gives a much higher assurance that the data is correct within +/-.

Reason #2; with the too small sample size the average velocities fall well within the expected ES in average fps results of even identical test strings, especially when tested in revolvers. Even with statistically valid 10 shot test strings the average velocity can well be within the ES +/-. The larger the test sample the closer to the true average velocity. Even then the average velocity of 2 seperate 20 shot test strings will probably not be the same either.

Reason #3; with the load density of Power Pistol in the large 45 Colt case the difference of .2 gr of powder may not be consequental enough to effect fps's outside of the normal variation of the individual 5 test shots of the test string.

Larry Gibson

[Potsy]

I wanna know why your 454424 will size to .454 when mine will hardly touch the sides of a .452 sizer die.
Not to be off topic, but every Lyman I've got (.45, .44, and .38, all Keith SWC) is undersized!
As for making loads hit to the sights, if I ever buy a Vaquero, it will make a trip to Mr. Bowen or Mr. Clements for a wee S&W adjustable rear sight.
Of course, I've never priced having that done. I might decide working up a fixed sight load is just more reloading "fun"!!!
OOPS! Just notices your gun is a Colt SAA, not a Vaquero. You Prolly don't want to have anyone screwing new sights on it in that case!
If you are hitting low, you might try 2400 or Blue Dot. I'm thinking the slower powder (heavier charge weight) might bring the muzzle up a little higher during recoil (even at the same velocity as the faster powders). Just a thought.

[Silver Jack Hammer]

I certainly have looked at having a S W rear sight milled into the top strap. Right now the pic on Clemonts website shows the finished job with an awful thin measure of metal left on that critical point of the frame. Both Keith and Skeeter loved their adjustable rear sighted Colts.

My 454424 drops .457" with 4 parts Linotype 6 pats wheel weights. Actually my wheel weight alloy is just a mix of what I get at the recycler.

[Silver Jack Hammer]

9.0 gr of Power Pistol drove the 454424 at 850 fps. 9.5 gr clocked at 898 fps. Two hand hold off hand 25 yards 5 shots of the 9.0 gr grouped at 1 3/4". Not bad for a factory 4 3/4 Colt .45. The problem is the group was 3 inches low, and that is a problem with fixed sights. All my Colt's .45's are zeroed for 454190 over 8.7 gr of Unique.

[ALM3kids]

Just got my hands on an older 454424. I want to size to 452 and shoot in both my lever gun and my Ruger 45 Colt. Suggestions on powder? I am looking for about 1100 FPS or there about. Looking at making this my brush gun load and my pig getter!

[Silver Jack Hammer]

Even 9.0 gr of Power Pistol showed erratic velocities with spreads of over 100 fps. The 9.5 gr of Power Pistol settled the charge right down to a consistent burn and propelled the 454424 at 900 fps.

I'm still working on a load for Power Pistol with my new 452432.