04-04-2011, 12:28 PM
Reno82 Wrote:I was just wondering..... since 7.63x39 can be necked down to a 6.5 grendel case could the 6.5 grendel with a 123 gr bullet do the same damage as the mother case. Non reinforced wall with standard building cement brick. I'll do a search on youtube and see what I come up with. Thanks for everyones input.
R82:
Remember that the Grendel case is only similar to the 7.62 X 39 case. The Grendel case has much more volume and that translates to velocity which is vital in terms of kinetic energy. Its mother case is not a 7.62 X 39 but rather a 6 PPC and in this case the differences are significant.
When you are talking about terminal ballistics and particularly penetration and residual penetration you must state the construction of the bullet, the impact velocity, obliquity angle, and if you can the yaw. Unfortunately. you must state very specifically the material, its dimensions, and its thickness. Sorry but otherwise a test can be rigged in favor of one cartridge.
Also, you must define very specifically the bullet construction of both or once again, such a test can be rigged in favor of one over the other. This is elemental to the question. There are many varieties of 120 and 123 grain bullets and a couple of variations of the bullet used for the 7.62 X 39. All will show different penetration properties. And lets say a 123 grain 6.5 bullet doesn't do as well as a 126 grain 7.62 X 39 but a 115 grain 6.5 bullet performs significantly better in all tests. What would the conclusion be then?
However, if your material is such that both penetrate it, then you need to look at the effect on what ever is behind that wall you are trying to hit. Called residual penetration and it is a lethality.
So, the question being asked lacks the types of specifics needed to provide an answer that is more than a 50 / 50 flip of the coin guess.
LR1955