Do I need to go much higher on BHN for better accuracy in my Pedersoli buffalo rifle?

[JimGnitecki]

Last evening I loaded up 50 cartridges:
25 of them with the BHN 15 alloy and .460" diameter bullets, and
25 of them with the BHN 15 alloy and .459" bullets

At my next range session, I will test a total of 3 different variants:
BHN 12.5 alloy with .460" diameter bullets
BHN 15 alloy with .460" diameter bullts
BHN 15 alloy with .459" diameter bullets

Note that:

My Pedersoli's barrel was slugged by the gunsmith as being .4563”

My Lee .460" sizing insert actually results in a bullet diameter that my digital Mitutoyo caliper, which displays a 4th decimal place only as either a "0" or a "5", consistently displays as .4595", which means that the actual sized diameter is slightly UNDER .460", and closer to .4595" than to .4600". So, the ".460" diameter bullets are actually at MOST .45974". So, the ".460" bullets are actually only at most .00344" larger than the barrel groove diameter.

Thus the .459" sized bullets, which the digital caliper displays as .4590" every time, are therefor only actually at most .45924". So, the ".459" diameter bullets are actually at most .00294" larger than the barrel groove diameter.

I do not have a .458" sizing insert to try.

IF the .459" sized bullets should prove to be more accurate, I will order a .458" sizing insert from Lee in The U.S. to try as well. (Not in stock anywhere in Canada that I could find).

By the way, the combination of the Brinell Hardness Calculator and a Rotometals "Super Hard" ingot made producing the BHN 15 alloy both reliably predictable and easy. SUCH an improvement over using wheel weights and other "mystery" materials.

Jim G

 

[AJC1]

Last evening I loaded up 50 cartridges:
25 of them with the BHN 15 alloy and .460" diameter bullets, and
25 of them with the BHN 15 alloy and .459" bullets

At my next range session, I will test a total of 3 different variants:
BHN 12.5 alloy with .460" diameter bullets
BHN 15 alloy with .460" diameter bullts
BHN 15 alloy with .459" diameter bullets

Note that:

My Pedersoli's barrel was slugged by the gunsmith as being .4563”

My Lee .460" sizing insert actually results in a bullet diameter that my digital Mitutoyo caliper, which displays a 4th decimal place only as either a "0" or a "5", consistently displays as .4595", which means that the actual sized diameter is slightly UNDER .460", and closer to .4595" than to .4600". So, the ".460" diameter bullets are actually at MOST .45974". So, the ".460" bullets are actually only at most .00344" larger than the barrel groove diameter.

Thus the .459" sized bullets, which the digital caliper displays as .4590" every time, are therefor only actually at most .45924". So, the ".459" diameter bullets are actually at most .00294" larger than the barrel groove diameter.

I do not have a .458" sizing insert to try.

IF the .459" sized bullets should prove to be more accurate, I will order a .458" sizing insert from Lee in The U.S. to try as well. (Not in stock anywhere in Canada that I could find).

By the way, the combination of the Brinell Hardness Calculator and a Rotometals "Super Hard" ingot made producing the BHN 15 alloy both reliably predictable and easy. SUCH an improvement over using wheel weights and other "mystery" materials.

Jim G

The noe sizing system is superior and has about every size you can immage. At 7.50 per insert it's my one and done solution. If you have shipping issues I'm sure he can call it a tool. I'll be in that sizing fight shortly with 45c.

 

[JimGnitecki]

The noe sizing system is superior and has about every size you can immage. At 7.50 per insert it's my one and done solution. If you have shipping issues I'm sure he can call it a tool. I'll be in that sizing fight shortly with 45c.

I like the overall Lee solution, which includes the clever red colored reservoir. Very easy to use. I went to the Lee website just half an hour ago and found that they have the .458" sizing insert in stock. I already have the reservoir setup plus the .459" and .460" inserts, past orders from them have arrived remarkably early (they must have a good customs clearing system), and the .458" die insert is just $16 US plus USPS postage. So I ordered it.

Jim G

 

[AJC1]

I like the overall Lee solution, which includes the clever red colored reservoir. Very easy to use. I went to the Lee website just half an hour ago and found that they have the .458" sizing insert in stock. I already have the reservoir setup plus the .459" and .460" inserts, past orders from them have arrived remarkably early (they must have a good customs clearing system), and the .458" die insert is just $16 US plus USPS postage. So I ordered it.

Jim G

I have both now, the storage is a fraction of the space for noe inserts. That became an issue when this southern humidity makes everything rust and I needed to keep it all inside... that is probably not a motivator in your area so I appreciate our differences in situation.

 

[JimGnitecki]

I have both now, the storage is a fraction of the space for noe inserts. That became an issue when this southern humidity makes everything rust and I needed to keep it all inside... that is probably not a motivator in your area so I appreciate our differences in situation.

Here's a photo of the actual Lee .458" die insert & punch:



You can't get any smaller physically!

the reservoir, die, and all the die inserts & punchs fit into the one 2.5" diameter x 8" high storage cylinder:



The Lee Breech Lock system enables me to snap the entire setup into and out of any standard threaded loading press in seconds. The reservoir holds at least 50 or more of even the large 500g bullets! But I am cautious about the weight building up in the reservoir when the bullets are THAT heavy and are deliberately soft versus hard, so I empty the reservoir after sizing 50 bullets.

Jim G

 

[AJC1]

Here's a photo of the actual Lee .458" die insert & punch:

View attachment 1176853

You can't get any smaller physically!

the reservoir, die, and all the die inserts & punchs fit into the one 2.5" diameter x 8" high storage cylinder:

View attachment 1176854

The Lee Breech Lock system enables me to snap the entire setup into and out of any standard threaded loading press in seconds. The reservoir holds at least 50 or more of even the large 500g bullets! But I am cautious about the weight building up in the reservoir when the bullets are THAT heavy and are deliberately soft versus hard, so I empty the reservoir after sizing 50 bullets.

Jim G

That's a new system. I have the old lee...

 

[JimGnitecki]

That's a new system. I have the old lee...

Yeah, I really like the new Lee sizing setup. I can do 50 bullets in just a couple of minutes, and the Setup and takedown are both incredibly fast and easy. GREAT concept and execution, and a reasonable price for everything needed. A lot of people don't realize that Lee came up with this new, better and cost efefctive solution.

Jim G

 

[Charlie98]

That must be a pretty recent change. I custom ordered a sizer for my .348WCF bullets, and it was nothing like that.

 

[AJC1]

Yeah, I really like the new Lee sizing setup. I can do 50 bullets in just a couple of minutes, and the Setup and takedown are both incredibly fast and easy. GREAT concept and execution, and a reasonable price for everything needed. A lot of people don't realize that Lee came up with this new, better and cost efefctive solution.

Jim G

The did a great job.knocking off noe for intellectual property

 

[JimGnitecki]

That must be a pretty recent change. I custom ordered a sizer for my .348WCF bullets, and it was nothing like that.

It IS a very recent change. I was unable to find any Canadian dealers that it had the new product already. I had to order from Lee in The U.S. directly, 2 or 3 months ago.

Jim G

 

[JimGnitecki]

The Labradar distributor replied to my email that asked why the Labradar was showing INcreasing velocities at extended ranges (225 and 250 yards!), versus velocities that should be DEcreasing. He said:
"You must disregard that data. You are asking it to do something beyond its capabilities."

That's reasonable, given that Labradar only claims a 100 yard range on its website.

Jim G

 

[JimGnitecki]

It appears that higher BHN might indeed be what I need to spend some time and effort exploring!

In prepration for today's range session, I analyzed my bullet quality as objectviely as I could. As I am still an amateur in bullet casting, my Extreme Spread on cast bullet weight is between 0.9% and 1%. My standard deviation is 1.2 grains (=0.25%). I'll get better with time.

Today's range session was encouraging:

Average velocity was 1393 fps, which is about a 35 fps increase versus the softer heavier bullets that were cast with the prior softer alloy. Upping the BHN meant upping the Antimony content, which reduced the cast bullet weight from 494g to just under 473g. The hardness after a couple of days was about BHN = 16, and did NOT decrease when I heated the bullets up to 450F for 2 minutes to melt the Eastwood powder on them, and then baked them for 20 minutes at 400F to bake the powder. I targeted BHN = 20, but the sample bullets I have been testing with the Lee Hardness Tester have not reached, at least yet, that BHN 20 target, despite my checking and rechecking my alloying math. I have to assume it simply does take more time than a couple of days for the alooy to harden to BHN 20. At east the one hardnes aging graph I have seen suggests that it can take at least a week to get to full hardness.

At 200 yards, the Labradar said they were still reliably supersonic, which means I'll be able to use my Shotmarker electronic tareget system with the Pedersoli rifle out to 200 yards. 225 yards MIGHT be possible, but the remaining velocity there is right around the speed of sound, so the Shotmarker might not catch some of the bullets at 225 yards.

Accuracy was improved today in 2 ways today over prior range shooting sessions:

1. The best 5-shot group fired today was 1.25" at 150 meters = 164 yards, which translates to 0.73 MOA at that range. Slowly getting closer to my target of 0.6 MOA.

2. There were no "wild" shots at all. Just groups not as good as the 1.25" group, but NO "flyers". That is a very significant improvement.

So, higher BHN did make a noticeable improvement.

This was with BHN = 16 (so far) and .459" sizing. Need to next try BHN = 20.

I will also, separately, try a batch of bullets sized to .458" versus .459", since the .458' did make a marginal improvement in reducing flyers over the prior .460" in a prior range test, That makes .458" worth trying, and the Lee .458" sizer insert and punch did arrive a couple of days ago, so I am ready to try the .458" sizing..

Jim G