Author Topic: Leading questions  (Read 621 times)

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Offline Iowa Fox

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Leading questions
« on: July 27, 2011, 10:25:44 AM »
A couple of weeks ago I made a range trip and encountered severe leading in a 44 mag barrel.
 
The gun is a Encore with 12" factory 44 mag barrel. Years ago I used a Lee scoop for 9.3 grains of unique- a ideal 429421 pure ww sized to .431 with LBT Blue soft. The first trip out and all after gave me groups in a 2" circle @ 50 yards with no leading. Same with 23 grains of H110 but the recoil is severe.
 
This last trip I made a few changes. First I used 8.3 grains of green dot. The loads were put together 2 years ago stored in a cool basement. I seated the bullets out very far since the throat is the forcing cone style to see if I could better accuracy.
 
The temp was about 92-93 degrees that day and the barrel patched dry. The groups opened to about 3 inches But the leading was horrible in the first 2 inches of rifling and about the last 3/4 inch at the muzzle.
 
I used a brush with copper chore girl to shave it out and just had little piles of lead dust and it just seemed welded to the barrel steel.
 
I know that experiment did not work and I can go back to what did. What has been bugging me is just what caused this.
 
My LBT tester says the 2 year old bullets are about 9-10 hardness.
Did seating the bullets out far create lower pressure problems in a forcing cone throat?
Do older cast bullets that have been loaded in a case for extended time  tend to lead?
can a forcing cone throat cause problems with certain powders?
Should a person try to use fresher cast bullets not ones cast a couple of years ahead
 
Not looking to try to make that combination ever work but just trying to figure out what happened to help with things to avoid in the future.
 
 
Just wondering what your thoughts are.
 
Thanks
 

Offline Veral

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Re: Leading questions
« Reply #1 on: July 27, 2011, 07:09:45 PM »
  Seating bullets out reduces the pressure if the powder charge isn't changed.    If you quench hardened your WW bullets they have lost a dramatic amount of hardness, but if you air cooled on a pad and let them pile up, the hardness is normal and probably didn't change.  If that was your cooling method, in the future, when cooling on a pad, keep the bullets well spread out till they are cool, and preferably have a small fan blowing across them, which will increase hardness without the hassle of water quenching.  If you consider quenching to be a hassle.  The most hardness stable bullets one can make are air cooled, and hardness will hold for many years.  Quenched WW will suffer hardness loss quite dramatically if stored in a hot place, but shouldn't lose much in two years in a cool basement.

  However, I believe your previously untested Blue dot load is the main culprit, with perhaps the relitively high temperatures be a second possible problem.

  I've never lived with the curse of having to drive to a range, but have always had a property where I can shoot out the back door of the shop, or walking distence from it.  I always load only a couple rounds of a new load, 5 at most, for initial test.  If driving to a range I'd load 5 rounds of what I knew was a light load. increase the load slightly and load five more, etc, etc, till I got up to what I thought might me the power I wanted or max.  Start shooting the light loads and quit with the lot that causes leading or blows accuracy.  Pull the remaining bullets when you get home, and you'll not have such a problem again in the future.   One problem though with pulling cast bullets is that gas checks normally stay in the case.  If using gc bullets make sure you don't load any rounds that might have to be pulled.

  You'd do better to drop the charge of H110 to get less recoil, and leading.  20 gr is a good sensible load and very stout in a 12 inch fixed barrel, and that much reduction will reduce recoil dramatically..
Veral Smith

Offline Iowa Fox

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Re: Leading questions
« Reply #2 on: July 28, 2011, 06:24:06 AM »
Thanks Veral