H-110 in 45 NM Blackhawk

[tullymars]

I just bought a NM Blackhawk convertible.I measured the chamber throats in the 45 colt cylinder and they are all .450.I want to try some Hornady 250gr XTP with 25 gr of H110. Is this going to cause any pressure problems with chambers this tight? Any comments or suggestions will be appreciated. Thanks guys.

[Fowler]

I think the best thing to do is send the cylinder to cylindersmith.com and he will cut the throats to .4525 for $30, it will make things simpler for yeas to come.

I think 25gr is a bit heavy for the gun even with proper throats. I have shot them at that point and even a bit heavier but I have settled on 24.0gr as my heavy 250gr load for hunting with light bullets, going heavier didn't really up my velocities much but the muzzle bast got a little rough.

[tullymars]

Thanks for the input Fowler. I haven't shot this gun yet but am going to run some hard cast 250s through it today. Imay let my local smith look at it and get his mearsurements also. If it groups well and doesn't lead badly I may forget about jacketed bullets for awhile.

[Fowler]

I ran my first Bisley with .4495 throats for a couple of years. I noticed the velocities were higher with the tigher throats by 30fps or so but accuracy was not as good as it was after I openned them up. I shoot 99.5% with cast bullets that I cast and I don't buy into the "bumping" theory for sealing the bases of the bullets in the bore. Yes it works but a properly sized bullet in proper sized throats is far more consistant and accurate in my experience.

On the other hand if yours shoots well with cast bullets and does not lead well whats not to like...

[tullymars]

Thanks for the help. Took it out to the range loaded with 250gr RNFP Laser.cast and 8gr Unique. No leading and good accuracy even with me behind it. Looks like life is good.

[dana]

Be advised the MINIMUM load with H110 and the 250 XTP published by Hodgdons is 25.7 grains. Which is 3% lighter than the maximum of 26.5 grs. See their warning. I use 26.0.

Dana

[tullymars]

Yes thanks, I double checked this load on Hogdon site. My initial data came from John linebaugh. Also my first measurement of the throats was not correct.

[COR]

Put down those stupid measuring tools and burn some gun powder! Now gas on it!

Gee Whiz...is this a measuring epidemic or something...SLOWLY STEP BACK FROM THE PLUG GAUGES...or calipers

[tullymars]

Knowing Rugers reputation for tight chambers I was concerned about high pressure with the jacketed bullets. Other than this particular gun, I've never measured for anything but curiosity.

[tullymars]

Sorry, I meant to say throats ,not tight chambers. I do know difference.