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jimmckee
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johnalbert
If I’m reading this correctly, both grease grooves of 0.020 CC each on the revised two groove design equal 0.040 CC lube capacity total. This about equals what one groove has on the original RCBS design (0.037 CC). Original RCBS would be 0.074 CC total.
The three groove iteration would have 0.017 X 3 or 0.051 CC total.
This lower capacity for lube with the two narrower shallower grooves is closer to what I’m after. Stronger bullet, substantially less lube. I would like to maintain bullet integrity most especially for the GC version at the higher pressure levels if the lube grooves are unfilled (some like to tumble lube occasionally like me) by tending any further changes toward shallower lube grooves as the deep grooves are tending to be the weak point of the design. The bottom lube groove is the most likely to distort under higher pressure permissible with gas check bullets if the lube groove is unfilled.
How about .235″ for the width of the bullet bottom of groove to bottom of groove and calling it good?
I should comment that….for those who are thinking that is all the lube there will be….. that the GC version will still have a little lube in the gap between the top of the gascheck and the band above the gascheck shank assuming there is a little room there as there usually is, and when processed through a lubrisizer or pan lubed.
With any good lube, and even with fairly poor lubes there was way too much lube capacity for smokeless powder loads with the RCBS bullet as-is.
peterogers
I agree with 35remington that a .235″ grease groove depth diameter would be even better for correct lube volume.
Actually if I was designing this bullet I would prefer that the two main body bands be shortened lengthwise from .085″ to .080″. Then I would add this .010″ to the base band width increasing it from .100″ to .110″ in the plain base version and from .050″ to .060″ in the gascheck version. The base is where we need the base band width for more resistance to gas cutting in plain base and additional strength for high velocity loads in the gascheck version.
I also think the gascheck shank diameter is undersize and should be checked for the final drawing. I think it needs to be changed from .239″ to .244″.
This would be an accurate and great hunting bullet.
2520WHV
SwedeNelson
I am on board with that including WHV’s changes. I like the thick base band as well as it is a known benefit and as I mentioned earlier I like the 258283 Lyman and the recent NOE 260283 with their thicker base bands. I put my money where my mouth was and ordered a 260283 from NOE, and in this run I’d like a mixed GC and PB mould, five cavity if I could get it, and 4 PB 1GC if I could get it so configured. I shoot more plainbase than gascheck but a gascheck design would be most appreciated in an RCBS design that has the weak points omitted.
If I couldn’t get 4PB 1 GC then I’d settle for a 3 PB 2 GC mould in five cavity.
Swede, much thanks for your responsiveness. It is appreciated.
davidlawrence
Group Buy started
http://noebulletmolds.com/smf/index.php?topic=421.msg2555#msg2555Thanks for the great input
Bullet maker, maker
Al Nelson
johnalbert
peterogers
SwedeNelson
teemu
tomelgan
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