Tony Williams Wrote:We know enough about bullet design to know that we can produce c.6.5mm military ball bullets with much better ballistic coefficients than the 7.62mm M80 (the Russians have been making much better shaped 5.45mm 7N6 bullets for four decades).No argument. I'm sure that 6.5mm military ball projectiles with higher BC can be made. It's just that until they are, we don't know what the actual BC will be. Therefore, to make comparisons using calculated BCs for hypothetical, but non-existent, bullets seems of little value to me.
Quote:Even if we assume that we can't improve on the 7N6 form factor, it is still easy to demonstrate that a 6.5mm military bullet can be made to deliver a ballistic performance out to 1000m which is at least as good as the M80, from a cartridge case which is significantly smaller and lighter and generates a lot less recoil.How can you demonstrate that without having a bullet to shoot???
Quote:In evaluating different calibres, ARDEC produced EPR-style bullets in each calibre and tested them thoroughly before concluding that calibres in the 6.35-6.8mm range offered the best characteristics. AMU came to the same conclusion after careful study.They may be right, but how do we know that? Do we know what their test protocols were? What bullet weights and muzzle velocities? Anything at all?
Quote:So there is plenty of data concerning the performance of the ammunition...Where is it? I haven't seen it.
Quote:...certainly enough to justify moving on to the next stage, which is working up prototype military ammunition in military guns for exhaustive testing in order to validate the concept.Why try to jump from theory to very expensive manufacturing and comprehensive tests? Why not first do relatively low-cost testing to check the viability of the concept? For instance, conduct long range, hit probability comparisons with a number of shooters using 5.56 and 6.5 Grendel versions of the M4 carbine? Or do tactical penetration tests with 6.5 Grendel and .308 Winchester using the same type bullets? Much more affordable, and would (assuming positive results) give hard data that should make it easier to "sell" the concept than paper calculations alone.
Quote:Stan, forgive me if I'm misreading you, but your attitude to this subject comes across to me as: "because we don't yet have a working military gun and military standard ammunition which have been tested to validate the concept, talking about it is a waste of time".That's not my position. I'm saying that comparing ballistics of, for example, 7.62 FMJ and 6.5 HPBT is a waste of time, because the latter will never be a general purpose Ball load for machine guns and rifles. I'm also asking why Grendel (and GPC) proponents seem to be so opposed to doing relatively simple and affordable comparison testing to validate their claims.
Quote:Like any project, this one is passing through stages, and the current stage is to demonstrate the calculated benefits in order to generate enough interest for people to move on to making the ammunition and guns for practical testing.Okay. So wouldn't it be more likely to gain the interest of those people if you provide hard data (from actual shooting tests) that confirms the calculated benefits?