You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
unstable heavy 44spl
- Thread starter Shadow9mm
- Start date
reynolds357
New member
Well aware. You can switch from brand to brand on primers and often see more drastic results than from mag to std or vice versa. I usually start with powder mfg recommended primer. With powder evolution, mag primers are less and less needed.Reynolds357,
The real test is to take your chronograph and check to see which primer produces the lowest SD and ES with your bullet and gun with this powder. That will be the one producing the most consistent ignition. The problem with less consistent ignition, in addition to the greater threat of getting a round that squibs out, is that it is associated with variation in exact time between firing pin strike and the bullet exiting the muzzle. This irregularity can be up to tens of milliseconds when it gets really bad, so it can have the same effect as having varying lock-time. It exaggerates the effect on group size by any imperfection in the shooter's steadiness and follow-through.
Shadow9mm,
Sounds like some of your bullets were being unbalanced by either gas cutting on one side or simply distorted by bullet tilt or by the bore engraving it with rifling marks unevenly. If there is any way you can recover some of the bad-behaving bullets, you should be able to see the cause.
Empirically, I have found shooting cast lead 0.002" over groove diameter often groups better than shooting lead 0.001" over groove. This depends on chamber dimensions, but if your mold will allow it, it is worth a try.
This may be apples and oranges, revolver to rifle. When I bought my Ruger Lipsey Special 44 SPL Bisley I read some articles by Ross Seifred testing the gun.
He ran into some accuracy problems rooted in a "throat choked" barrel. Something about turning and threading the barrel shank and screwing it in the frame had "swedged down" the bore/groove dia. at the breech end of the barrel. Any bullet was being sized down passing through.
A rifle is different as the barrel shank surrounds chamber not barrel throat,as in a revolver.
The revolver remedy may not apply. But Ross achieved significant accuracy gain by fire lapping the constriction out. Thats not exactly a recommendation.
Who knows what may help?
As far as cast bullet flaws,solidifying liquid metal shrinks at a given rate. It first solidifies an outer skin,as the heat transfers to the mold. The hardening of the skin limits the movement or sink of the outer diameter. The center remains liquid. So the accumulated shrink/sink will stack up to create void or porosity in the center of mass of the bullet. More or less.
You may be finding a can of worms in shrink/sink/ voids and cooling of your cast bullets and casting technique.
A man who has written a few books and pursued casting bullets for 45-70,etc is Paul Matthews.
Its been years since I read it, and I can't even tell you which of his books, but I do recall he could not get results with a bottom pour pot. As I recall he recommended a ladle with a pour spout of 2 or more pounds capacity. I don't recall the exact details,but sustaining fill pressure at the sprue as the bullet solidified improved bullet integrity. IIRC he poured over the sprue plate.
Just popping the bullet out to cool on its side may not be best. Some folks drop them from the mold to a bucket of water.
If I was cooking up a 44 spl/ Mag deer load...Maybe I'd go with a shorter ogive Keith 240 (or so) gr SWC . Short ogive so you can load 44 magnum cases with no feed problems. I'd cast wheel weight.Maybe add a trace of tin (lead free solder) for better casting quality. Probably I'd use gas checks.
Then(for myself) I'd load published zippy H-110 loads and figure on accurate loads that will pass through the deer. But thats me. YMMV
He ran into some accuracy problems rooted in a "throat choked" barrel. Something about turning and threading the barrel shank and screwing it in the frame had "swedged down" the bore/groove dia. at the breech end of the barrel. Any bullet was being sized down passing through.
A rifle is different as the barrel shank surrounds chamber not barrel throat,as in a revolver.
The revolver remedy may not apply. But Ross achieved significant accuracy gain by fire lapping the constriction out. Thats not exactly a recommendation.
Who knows what may help?
As far as cast bullet flaws,solidifying liquid metal shrinks at a given rate. It first solidifies an outer skin,as the heat transfers to the mold. The hardening of the skin limits the movement or sink of the outer diameter. The center remains liquid. So the accumulated shrink/sink will stack up to create void or porosity in the center of mass of the bullet. More or less.
You may be finding a can of worms in shrink/sink/ voids and cooling of your cast bullets and casting technique.
A man who has written a few books and pursued casting bullets for 45-70,etc is Paul Matthews.
Its been years since I read it, and I can't even tell you which of his books, but I do recall he could not get results with a bottom pour pot. As I recall he recommended a ladle with a pour spout of 2 or more pounds capacity. I don't recall the exact details,but sustaining fill pressure at the sprue as the bullet solidified improved bullet integrity. IIRC he poured over the sprue plate.
Just popping the bullet out to cool on its side may not be best. Some folks drop them from the mold to a bucket of water.
If I was cooking up a 44 spl/ Mag deer load...Maybe I'd go with a shorter ogive Keith 240 (or so) gr SWC . Short ogive so you can load 44 magnum cases with no feed problems. I'd cast wheel weight.Maybe add a trace of tin (lead free solder) for better casting quality. Probably I'd use gas checks.
Then(for myself) I'd load published zippy H-110 loads and figure on accurate loads that will pass through the deer. But thats me. YMMV
Bore constrictions where barrels screw into the frames of revolvers are common, and might even reflect most revolvers as they come from the factory. Lots of folks either firelap or hand lap them out. The cause is mainly that when you screw any barrel with a shoulder into any receiver and tighten its shoulder against the frame or receiver ring, all the engaging threads try to stretch the barrel threads away from the shoulder and compress the receiver threads toward it. But the threads furthest from the shoulder apply the same number of degrees of rotation up the thread helix to a greater threaded length of steel than the first thread near the shoulder does. As a result, that first thread is has a much greater load than the last thread does. It tries to relieve some of the stress by slipping off the slope of the V-thread profile, and slipping off directs the barrel threads inward, creating the interior constriction. That is maximized right under that first thread, and it continues to a diminishing degree as you follow the threads toward the breech. It is one reason for the ACME threads in some designs to minimize the slope. A square thread would prevent the issue completely, but square threads don't center a thing exactly and allow it to shift a bit with practical tolerances.
More modern spherical powders are less likely to require a magnum primer with their newer deterrent chemistries. But Hodgdon told me the older St. Marks spherical powders are still ordered with the exact same chemistry specified in the 1960s. They are not updated.
More modern spherical powders are less likely to require a magnum primer with their newer deterrent chemistries. But Hodgdon told me the older St. Marks spherical powders are still ordered with the exact same chemistry specified in the 1960s. They are not updated.