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GSSP
07-22-2009, 03:42 PM
About a month back I was working on developing load/s for my 4-5/8" SS, Ruger NMBH in 45LC. Bullet is LBT 280 gr WFN/pb/ 14 BHN wheel weights, air cooled. Lube is White Label BAC. Starline brass, Fed 150 primers. I went through Titegroup, Power Pistol and one other powder. Barrel mic's .451. Throats mic .452" each. Use RCBS .452" sizer die to get .453" finished bullet diameter. Around 9 gr of Titegroup I started to get a little leading @ 1038 fps. It only got worse with each .5 gr increase to 10.5 gr max.

Present day; I obtained some LBT Soft Blue lube. Kept everything the same. Again, leading at 9 gr/1059 fps and only got worse with each additional .5 gr charge.

Suggestions if you please? I'm thinking of water quenching my WW's or using LBT bore lap to smooth any barrel problems.

Alan

Wally
07-22-2009, 03:48 PM
I have a Ruger Blackhawk in the .45 Colt---same dimension as what you have...I size my bullets to .454" and they chamber easily---I do get some minor leading...and use 7.0 grains of HP-38 with a 255 grain RCBS Keith cast bullet. Perhaps you should try youirs w/o sizing, if they fit in the chamber.

fredj338
07-22-2009, 04:08 PM
Try changing powders. I hear leading issues w/ TG, it burns very hot, melts the lube before it can come into play. I have fine reuslts in my Ruger using Unique for all bullet wts to 300gr & vel. to 1100fps or so for aircooled ww.

44man
07-22-2009, 04:26 PM
I don't believe those measurements, just how did you measure? Never seen a Ruger barrel that small.

Wally
07-22-2009, 04:31 PM
Mine was larger when I bought it. The ejector screw head broke off. I had to return it to Ruger---I attached a letter asking that should they replace the barrel & cylinder that they be of suitaible dimensions---.451" in the barrel & .451~.452" in the cylinder chamber mouth---well, they did what I had asked. The original cylinder was in the .455~.456" range.

Char-Gar
07-22-2009, 04:48 PM
Wally... Where in the barrel is the leading? Leading in the rear of the barrel makes on look at the forcing cone and bullet fit. Leading in the half nearest the front sight makes on look at lube issues.

There is of course the every possible rough bore caused by mico machine hickies. A good bore slicking and polishng will take those out.

Water quenching won't cure your problems, more likely make them worse.

I am not famililiar with you powder, but am familiar with the 45 Colt round and with Unique, 4227 or 2400 leading should not be a powder issue at your speeds.

Most any decent lube is good for 1K fps.

Wally
07-22-2009, 05:03 PM
Charger..I think you meant to ask GSSP...

243winxb
07-22-2009, 05:03 PM
Go to a slower powder. Add 2% tin to the alloy. From Lee -
Cast bullet leading

A clue to what is causing the leading is where the leading first begins to appear. If it appears near the chamber, chances are that bullet diameter or hardness are the cause.

A diameter too small and/or too hard an alloy will allow high pressure gas to leak past the bullet, which erodes the bullet and leaves leading near the chamber.

If the leading first appears on the leading edge of the rifling (if you imagine the bullet being pushed through the barrel, you will note that one edge of the rifling does most of the work of imparting a spin to the bullet. This is the edge you see when you look through the barrel from the breech end) the bullet might be too soft, and/or the velocity too high.

If the leading appears in the second half of the barrel, the bullet is running out of lube. You should see a star shaped pattern of lube accumulate on the muzzle. This is an indication that there is a little excess lube.

Rico1950
07-22-2009, 07:08 PM
Have a blue 5 1/2" NMBH in 45 Colt that shoots fine now.
Recut forcing cone to 11 degrees and used LBT bore lapping cmpd. No more leading.
Barrel is .451", cylindersmith opened up the throats to .452".

Whitespider
07-22-2009, 07:17 PM
Go to a slower powder.

I concur wholly, a slower powder and make sure you don't have a constriction in the barrel at the frame.

GSSP
07-22-2009, 07:42 PM
44 Man,

I carefully cleaned and lightly oiled both barrel and cylinders. Then I took Hornady .457" round lead balls, oiled them up and gently drove them through or into and out of the barrel, throat and muzzle with a hardwood rod. Kept coming up with .451". Did the same with each throat. Measured each sized lead ball with my Mitutoyo 6" dial caliper that reads to .001". Did this at least 3x each and kept coming up with same numbers.


My stainless steel Ruger NMBH came out the factory door April 1996 per a tele call with Ruger if that matters.

Chargar,
With the 9 gr loads the leading started near the forcing cone end but as the powder charges increased the leading was found through out the entire barrel length.

I have plenty of different powders and can easily try slower one for the faster velocites I will need to make the Utah minimum of 500 ft lbs @ 100 yds. Should need approximately 1000 fps.

Alan

243winxb
07-22-2009, 08:49 PM
Barrel mic's .451. Throats mic .452" each..453" finished bullet diameter. The bullet is bigger than the throat, is that a problem?? I have no experence with this as i dont measure throats.

Catshooter
07-22-2009, 09:31 PM
I run my wheel weight air cooled Keith 255 grain SWCs over #2400 to 1570 fps out of my Winchester Trapper. I've got about 150 rounds through it with zero leading.


Cat

runfiverun
07-22-2009, 10:14 PM
slow down the powder.
titegroup is in the 231 burn rate range.
i have used it up to 8 grs with no problems but always went to a slower powder after that point.

GSSP
07-22-2009, 11:58 PM
Ok guys. I've got plenty of Universal, HS-6, H110 (16 lbs each), 296, etc. I get the message.

Alan

GSSP
07-25-2009, 07:24 PM
I did two things to my Ruger. First, yesterday am I ran 100 lapped bullets through my gun. Veral's suggestion is to run 1.5 to 2.5 grs of either Bullseye or 700x. I have both and selected 2 grs of 700x. Of the 100 rounds, 5 stuck in the bore. I was prepared. Brought several 8" lengths of hardwood dowels in 1/2" diameter and a heavy hammer. Got them out with out a hitch and an extra pair of hands to hold the gun. Next time, if their is a next time, I'll run more than 2 gr of 700x. I could look over the sights and easily see the bullet lobbing it's way towards my target; a simple steel plate which helped me know the bullet had successfully departed the barrel with a light "tink".

Then this am I ran another 100 rounds. Half with Universal and 1/2 with HS-6. Hit 1012 fps with the Universal and leading was minimal with a great group. Hit 1030 fps with the HS-6 and, again, had minimal leading.

Had some left over hot loaded Titegroup loads which hit 1138 fps and left a ton on lead in the bore. Oh well, I guess Soft Blue can't fix leading due to overpressure loads.

To be honest, I'm not sure if it was the slower powder or the lapping that helped my situation. It was probalby a combination of both.

Alan

Rico1950
07-25-2009, 11:32 PM
If your getting minimal leading after 50 rounds I personally would not worry about it.
Was the accuracy still there with the minimal leading?

44man
07-26-2009, 08:53 AM
All of you know how I feel. The faster the powder, the harder the boolit needs to be. With the punch in the butt those boolits are getting I would be shooting 25 to 30 BHN.

GSSP
07-27-2009, 08:13 PM
Things are getting better.

This am I ran some low end loads of both H110 and Lil-Gun with both air cooled and water quenched WW's. Speeds hit 1100+ fps with zero leading. Accuracy with 10 shot groups was between 1"-2" @ 25 yds.

FYI, the reason I started with Titegroup is an 8lb jug I have. I also have two each 8 lb jugs (16 lbs each) of Universal, HS-6 and H110. These were "given" to me:mrgreen:. Include the "free" wheel weights and my ammo costs $.03 each to shoot with Fed 150 primers. Gosh I LOVE shooting cast boolits!:drinks:

Alan