43-287B
- Thread starter Brad
- Start date
Wow, the bullets with monotype added are way harder than I expected. Monotype may well be foundry type. These suckers are running 28-30 BHn.
Sized some to .431 and will see if I can get out Friday. Temps should be fine but wind is going to be a bit of an issue.
I also had cast some from the Lee 434640 mould I got from Glen. Those are same alloy so I can see what they do.
Did I mention these things are hard?
Sized some to .431 and will see if I can get out Friday. Temps should be fine but wind is going to be a bit of an issue.
I also had cast some from the Lee 434640 mould I got from Glen. Those are same alloy so I can see what they do.
Did I mention these things are hard?
Rick will kill me for an extra variable but.....
I used a different sizer for these. These were sized with the die I made for the 624 as the one for the SRH tended to lead the beginning of the rifling in the 624. Not but .0007 difference by my measurement but that can make all the difference in the world.
The larger size was a snug slip fit in all but the one cylinder throat. These are definitely a looser fit.
Were the bullets getting some damage in the cylinder throats? A few very low pressure slugs show no damage but we all know that high pressure moves metal.
I used a different sizer for these. These were sized with the die I made for the 624 as the one for the SRH tended to lead the beginning of the rifling in the 624. Not but .0007 difference by my measurement but that can make all the difference in the world.
The larger size was a snug slip fit in all but the one cylinder throat. These are definitely a looser fit.
Were the bullets getting some damage in the cylinder throats? A few very low pressure slugs show no damage but we all know that high pressure moves metal.
Targets are nothing special but recovered bullets are interesting.
287B
Lee 434640 plain base
These are hard, like 28 BHn air cooled and aged a month. Notice how much less the grooves are smashed?
Need to get the chrony data off the Lab Radar but it seemed the velocities were a bit lower than I was getting with the softer alloy. Bet these didn't obturate as well and some gas was lost.
287B
Lee 434640 plain base
These are hard, like 28 BHn air cooled and aged a month. Notice how much less the grooves are smashed?
Need to get the chrony data off the Lab Radar but it seemed the velocities were a bit lower than I was getting with the softer alloy. Bet these didn't obturate as well and some gas was lost.
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fiver
Well-Known Member
the targets are poor I bet.
look at the bases, your not engraving the rifling even close to straight.
on one side they look pretty good, on the other you can't even tell you have gas checks.
the difference in the engraving on the crimp groove and the nose shows the same thing.
you goin in there all kinds of crooked.
look at the bases, your not engraving the rifling even close to straight.
on one side they look pretty good, on the other you can't even tell you have gas checks.
the difference in the engraving on the crimp groove and the nose shows the same thing.
you goin in there all kinds of crooked.
The targets were interesting. A few shots on center then a shallow arc from 11 to 7 o'clock about 3-4 inches out. Not a straight vertical but a gentle arc.
And Fiver, the top bullets are the 287B, the bottom are the Lee GB 434640 plain base. Not the same bullets in the two photos. Sorry, should have labeled them.
And Fiver, the top bullets are the 287B, the bottom are the Lee GB 434640 plain base. Not the same bullets in the two photos. Sorry, should have labeled them.
Ian
Notorious member
You're still crooked. I think that's a gun problem more than anything else.
You also have lead-plated gas checks, which is too damn much pressure. If it takes a 28 bhn AC alloy to not collapse when shot, your pressure is STILL too high says me.
The only thing I know for you to try at this point is to back the pressure off and start with some comfy Unique or 2400 loads using your softer bullets. If you stress the system less it may work better.
You also have lead-plated gas checks, which is too damn much pressure. If it takes a 28 bhn AC alloy to not collapse when shot, your pressure is STILL too high says me.
The only thing I know for you to try at this point is to back the pressure off and start with some comfy Unique or 2400 loads using your softer bullets. If you stress the system less it may work better.
Easy to do. I just wanted to see what happens with a harder alloy today. Now I know.Someone mentioned in these 35 pages and in PM's to try isolating one of the two aligned throats & shoot only it as a test. Or not I guess.
I just need to find those in alignment chambers and mark them. For fair compairison will likely use the same load.
Should do that, surprised you haven't. Single best/easiest test to confirm how much of group size and bent screwed up bullets is the dimensions of the revolver. I think you will be surprised. All this did today was confirm yep, bullets still bent and groups aren't there. But then you already knew that.
But I also know that harder bullets will reduce the deformation due to pressure. That tells me misalignment is playing a role.
I did use just 5 chambers for all shooting today. The tightest throats was not used. Gotta love a Sharpie for marking stuff.
I did use just 5 chambers for all shooting today. The tightest throats was not used. Gotta love a Sharpie for marking stuff.
Cast 125 yesterday to ship to someone else for some testing. I had forgotten how easy casting this mould is. Bullets fall out easily, bands fill well, and it drops nice round bullets. While I have a few other moulds from Tom this one has to be one of the finest casting moulds I own.
This is my first Al mould from To but I don't think it will be my last.
This is my first Al mould from To but I don't think it will be my last.
Monday AM it was 60 at 7 AM. By 11 the wind was picking up and by 5 it was in the 30s with 20 plus mph winds.
The forecast doesn't look like good range weather the rest of the week. 35 isn't bad for shooting except when coupled with 15 mph winds.
The forecast doesn't look like good range weather the rest of the week. 35 isn't bad for shooting except when coupled with 15 mph winds.