“[With Leverevolution in the 30-30] we see a big performance gain of 240 fps over the fastest factory 150 gr ammunition and a 100 fps gain over the best reload with normal powder. All with less psi and better internal uniformity.” - Larry Gibson
So, my thesis is that Leverevolution may offer 100 - 200 fps velocity improvements over existing handloads while remaining within the 40,000 psi SAAMI pressure set for the Krag Joergensen rifle. I would appreciate a constructive review of my thinking and any relevant personal experience. Given that I do not have a pressure test barrel, the goal is simply to demonstrate a conservative improvement within pressure parameters (case head expansion method) and use that to encourage Hodgdon to do the testing for LVR with the 30-40.
We have data from Hodgdon for LVR in the 308 ME, with case capacity @ 6 grs less, +/- 2 grs depending on brass, than the 30-40 that puts the starting charge of 39 grs LVR/170 gr FP for 2,392 fps 37,400 psi. By comparison, in the 30-40, with a starting charge of 35 grs H4895 and 180 gr SP, MV is given as 2,171. No pressure rating for this charge is given in the Hodgdon data but we may assume it is somewhere well below the SAAMI 40,000 psi MAP, probably in the 33,500 - 35,000 psi range. Yes, this is an apples to Volkswagons comparison, but we have to start somewhere.
We see that with the 170 gr FP the starting charge for the 308 ME with H4895 is 35 grs, delivering 41,000 psi and 2,289 fps MV, or just over 100 fps less than the starting charge of LVR, in line with Larry Gibson's excelllent summary of Leverevolution's performance. But we must also notice that the same starting charge of H4895 in the 308 ME with a bullet 10 grs lighter delivers 1,000 psi over the SAAMI MAP for the 30-40 Krag. Therefore, that substantial case capacity difference also delivers a substantial pressure differential. Now we are comparing apples to another, albeit unknown, fruit. This is almost like progress.
So far, the same starting charge of the same powder in the 308ME with a 10 gr lighter bullet delivers something like 6,000 - 8,000 more psi than in the 30-40. This establishes, to my thinking a baseline safety parameter.
The next safety parameter is to not test in a 120 year old rifle with its notoriously weak single locking lug. Instead, I intend to conduct this experiment with a Ruger No.3, sharing the same falling block action in which the 416 Ruger and 375 H&H at 62,000 psi are chambered. While one ought not assume one's Ruger No 3 with an undoubtedly lighter barrel is rated to 62,000 psi, I am comfortable in assuming it is rated to a much higher pressure than an 1896 Krag Jorgensen rifle.
The third safety parameter is to test only to just under the 308 ME max charge of 41.4 grs LVR.
The control group will be 10 cartridges of H4895 loaded with 38.0 grs under the 180 gr Speer Hot Cor SP. This should deliver somewhere near Hodgdon's claimed 2,265 fps MV and case head expansion should be the max compatible with the Krag's 40,000 psi MAP.
The base group will be 10 cartridges loaded with the 308ME start load of 39 grs LVR under the same 180 gr Speer Hot Cor SP. Will inspect primers for pressure signs (or backing out,though unlikely) and measure case head expansion as a pressure indicator.
The third group will be 10 cartridges loaded with just under the max 308ME charge at 41 grs LVR under the same Speer Hot Cor 180 sp. Primers will be inspected and case head expansion recorded.
My expectations are that there will be no pressure signs in the Base group (39 grs LVR) and that it will be somewhat insipid as a load, while the 41 grs LVR will yield somewhere upwards of 100 fps over the control group with no case head expansion beyond that in the control group.
This is, admittedly, a pretty tame experiment but hopefully it demonstrates enough potential to get the pros at Hodgdon to have a go at Leverevolution in the 30-40. I predict that they will find a more than 100 fps gain vs other powders within the 40,000 psi MAP for the Krag and that we will have a load that yields a Maximum Point Blank Range of 225 - 240 yards with a 180 gr bullet from the Krag-Joergensen rifle, reestablishing its suitabillity for mule deer and elk.
So, a conservative experiment studying an arcane cartridge with a very modest goal. Nothing to get excited about, I agree. But if you have anythiing constructive to add, I would appreciate it. Thanks very much.
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