BK7saum
11-21-2012, 12:37 PM
I recently started casting the 247 whisper bullet. I have been hand loading for 25 years with J-words and the occasional cast boolits. But am basically a noob when it comes to the serious casting and loading.
I was wanting an alloy to open up or mushroom at subsonic velocity and decided to try 3:1 Pb to COWW with 1% tin. The allow cast fairly well but is obviously soft, maybe too soft for my purposes. ( I understand I might need to smelt a new alloy at 50/50 or 2:1 ).
Another possible problem I have is the Lee sizing die (.309 nominal). With this soft alloy, the bullet is being sized .3084-.3085. One question, will a harder alloy size larger. I'm about ready to polish the ID and open it up to .309 or .3095. BTW my barrel slugged out right at .308 for groove diameter.
I may have shot myself in the foot(figuratively, of course) in that I didn't clean the bore. I just wanted to verify if the bullets would stabilize and ended up with serious leading. The leading was prevalent in the first 8-10" of the 16" rifle barrel.
The rifle is a 16" 300 whisper with a 8 twist shilen barrel.
Oh, I am using the 45/45/10 recluse tumble lube.
I was also using two fast pistol powders, American Select and also Unique. The loads, around 6-6.5 grains gave velocities in the 950 to 1025 range. (I realize that a slower powder might/should work better with a softer allow, and that is something I plan on doing if I stick with this allow. I currently have 25 pounds mixed up). My understanding is that the slower powder (I have 1680 on hand) will give a slower push to the bullet and might allow it to engage the rifling without skidding and subsequent leading.
SO.....I have several things going on
1: A fouled bore, powder and copper jacket fouling.
2: A soft allow (can scratch with a thumbnail)
3: A fast twist rifling
4: Possibly undersized bullets for my application
5: A fast powder with a rapid peak pressure, possibly causing bullets to skid.
The testing
The first shot was stable and left a round hole (15') (I didn't check the barrel for leading and believe that the barrel leaded with the first shot)
The second and third shots keyholed (I checked for leading and found significant leading in the breech half of the barrel)
The fourth and fifth shots (with gas checks) were stable and left a round hole (15'). I was trying to cut some of the leading out with the checks, but it was a nogo. There was still signifcant leading in the barrel.
I do appreciate any insite from the wealth of knowledge on this board. I have identified places to start. The barrel has been scrubbed and is clean.
Should my first step be to retry this allow sized to the .3084" diameter, gas checked (or unchecked), with Recluse lube and see if it works without leading (in a clean bore)
Or should I use a new 50:50 allow and start fresh?
Do I need to open up the ID of the die to .309"+ before sizing any more boolits and testing?
I know I have a lot of questions. I am only trying to learn and hope to not have to make all the mistakes myself. Thanks for you patience and any wisdom, suggestions, and ideas.
Brad
I have read A LOT on this forum over the last few months/year, and know that some (probably all) of this has been covered here and there. I have read threads over alloy, bullet size to bore diameter, lubing, powder choice, etc, and don't think I've missed too many of them. However, I hate cleaning a leaded barrel, especially a rifle barrel, and any help that gets me to a good, workable load that doesn't lead sooner rather than later saves me from cleaning and recleaning a leaded barrel. Thanks, again.
I was wanting an alloy to open up or mushroom at subsonic velocity and decided to try 3:1 Pb to COWW with 1% tin. The allow cast fairly well but is obviously soft, maybe too soft for my purposes. ( I understand I might need to smelt a new alloy at 50/50 or 2:1 ).
Another possible problem I have is the Lee sizing die (.309 nominal). With this soft alloy, the bullet is being sized .3084-.3085. One question, will a harder alloy size larger. I'm about ready to polish the ID and open it up to .309 or .3095. BTW my barrel slugged out right at .308 for groove diameter.
I may have shot myself in the foot(figuratively, of course) in that I didn't clean the bore. I just wanted to verify if the bullets would stabilize and ended up with serious leading. The leading was prevalent in the first 8-10" of the 16" rifle barrel.
The rifle is a 16" 300 whisper with a 8 twist shilen barrel.
Oh, I am using the 45/45/10 recluse tumble lube.
I was also using two fast pistol powders, American Select and also Unique. The loads, around 6-6.5 grains gave velocities in the 950 to 1025 range. (I realize that a slower powder might/should work better with a softer allow, and that is something I plan on doing if I stick with this allow. I currently have 25 pounds mixed up). My understanding is that the slower powder (I have 1680 on hand) will give a slower push to the bullet and might allow it to engage the rifling without skidding and subsequent leading.
SO.....I have several things going on
1: A fouled bore, powder and copper jacket fouling.
2: A soft allow (can scratch with a thumbnail)
3: A fast twist rifling
4: Possibly undersized bullets for my application
5: A fast powder with a rapid peak pressure, possibly causing bullets to skid.
The testing
The first shot was stable and left a round hole (15') (I didn't check the barrel for leading and believe that the barrel leaded with the first shot)
The second and third shots keyholed (I checked for leading and found significant leading in the breech half of the barrel)
The fourth and fifth shots (with gas checks) were stable and left a round hole (15'). I was trying to cut some of the leading out with the checks, but it was a nogo. There was still signifcant leading in the barrel.
I do appreciate any insite from the wealth of knowledge on this board. I have identified places to start. The barrel has been scrubbed and is clean.
Should my first step be to retry this allow sized to the .3084" diameter, gas checked (or unchecked), with Recluse lube and see if it works without leading (in a clean bore)
Or should I use a new 50:50 allow and start fresh?
Do I need to open up the ID of the die to .309"+ before sizing any more boolits and testing?
I know I have a lot of questions. I am only trying to learn and hope to not have to make all the mistakes myself. Thanks for you patience and any wisdom, suggestions, and ideas.
Brad
I have read A LOT on this forum over the last few months/year, and know that some (probably all) of this has been covered here and there. I have read threads over alloy, bullet size to bore diameter, lubing, powder choice, etc, and don't think I've missed too many of them. However, I hate cleaning a leaded barrel, especially a rifle barrel, and any help that gets me to a good, workable load that doesn't lead sooner rather than later saves me from cleaning and recleaning a leaded barrel. Thanks, again.