Velocity loss
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Velocity loss
i suppose this topic has been discussed in a prior thread, but i couldn't find one so, a long time ago i purchased a hornady moly kit with the intention of mollying. but i never kept it up as other people had different ideas. anyway, i have been thinking about it again and once more read through the handbook that came with the kit. they claim that mollying will cause a loss of velocity. i am currently using a .223 1 in 7 twist rifle. my loads are lapua match cases, 80gr. smk projectiles being pushed out with 24 grs. ar2206h powder. adi powders guide tell me that i should be getti9ng 2825 fps. now if i moly how much velocity will i lose??
SHOOT WELL & SHOOT TRUE
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G'Day Whippy,
I dont know how much velocity you will lose but just treat the bullets as a "new type" and work up a load until you get the same accuracy. In a 6PPC, I've found it to be not much more than say 0.3 -0.5 gns more of the same powder to achieve the same level of accuracy.
You need to reproduce the barrel/action vibrations/patterns of the bare bullet load to the same level (intensity/energy??) since they WILL change with the lower velocity caused by moly bullets with the same powder charge.
Moly is a dry lube that allows the bullet to slip down the barrel a bit easier and this drops the chamber pressure and bullet time in the bore and as a consequence the vibrations change. Thats why you need more powder to recreate the accuracy/vibration patterns.
Essentially you have to go back and work up a new load, but start from your old load as you know it will be close to the new load you will need for moly bullets.
You're cleaning regime must stay the same to remove the carbon build up too. Otherwise it is all for nothing.
Hope this helps
Cheerio Ned
I dont know how much velocity you will lose but just treat the bullets as a "new type" and work up a load until you get the same accuracy. In a 6PPC, I've found it to be not much more than say 0.3 -0.5 gns more of the same powder to achieve the same level of accuracy.
You need to reproduce the barrel/action vibrations/patterns of the bare bullet load to the same level (intensity/energy??) since they WILL change with the lower velocity caused by moly bullets with the same powder charge.
Moly is a dry lube that allows the bullet to slip down the barrel a bit easier and this drops the chamber pressure and bullet time in the bore and as a consequence the vibrations change. Thats why you need more powder to recreate the accuracy/vibration patterns.
Essentially you have to go back and work up a new load, but start from your old load as you know it will be close to the new load you will need for moly bullets.
You're cleaning regime must stay the same to remove the carbon build up too. Otherwise it is all for nothing.
Hope this helps
Cheerio Ned
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- Posts: 46
- Joined: Sun Oct 14, 2007 3:46 pm
- Location: nsw south coast
ned kelly wrote:G'Day Whippy,
I dont know how much velocity you will lose but just treat the bullets as a "new type" and work up a load until you get the same accuracy. In a 6PPC, I've found it to be not much more than say 0.3 -0.5 gns more of the same powder to achieve the same level of accuracy.
You need to reproduce the barrel/action vibrations/patterns of the bare bullet load to the same level (intensity/energy??) since they WILL change with the lower velocity caused by moly bullets with the same powder charge.
Moly is a dry lube that allows the bullet to slip down the barrel a bit easier and this drops the chamber pressure and bullet time in the bore and as a consequence the vibrations change. Thats why you need more powder to recreate the accuracy/vibration patterns.
Essentially you have to go back and work up a new load, but start from your old load as you know it will be close to the new load you will need for moly bullets.
You're cleaning regime must stay the same to remove the carbon build up too. Otherwise it is all for nothing.
Hope this helps
thanks ned. this is a great help. will do it.
Cheerio Ned
SHOOT WELL & SHOOT TRUE
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