By Alex Pummer
So my first trip with the 7mm VAR was pretty productive. My main goal was to collect data for future loading and get a feel for the cartridge. I provided the targets for the hell of it, since some of the ladder tests shot better than my 5.56 AR. So I am really liking the X-Caliber barrel.
Initial impressions on the powders are as follows. LeveReloution : Still need to test more, but so far I like it. 8208 XBR : Its reputation for accuracy was seen pretty early on with the. Even with the ladder test 140 TTSX wasn't terrible. CFE223: This is a powder that should be avoided on barrels longer than 20", although if you have a mild charge on a 20" barrel you could still produce the double pressure spike. Please reference String 11 and notice shot 10 has a double pressure spike that almost mirror each other.
I have attached a chart of Optimal Barrel Times for different barrel lengths. (If you would like the Excel file, let me know.) It will provide reference for the exit time for images Pressure Spike 1 & 2. So in theory you should be ok with a shorter barrel, something I would want to confirm.
Rem 7 1/2(Lot#986) seems to be the goto primer, as CCI 450 & Wolf KVM-223M would produce double pressure spikes. Even though the Muzzle Velocity of CCI 450(Lot#K16U11) & Wolf KVB-223M (Lot#1-10) were slightly better than Rem 7 1/2. Reference String 1-3, these were my primer comparisons. String 4 A & B were actually shot first, to sight in the rifle & initial function check / troubleshooting.
With the rifle I did have some issues, FTE & FTF. The Failure to Extract was from the bolt cycling too fast. I was using a standard Carbine buffer. Forgot to bring my H3 buffer which I think would have solved the issue. Lost 3 brass to cycling issues, necks were too badly damaged for me to salvage. But in most cases the brass was turned around in side the ejection port area, and as my firing went on, the brass would just sit in the ejection port area. Glad I brought my Bob Led Sled, which allowed me to finish the day out at a slower pace. The Failure to Fire could have been 1 of 2 possiblities, the Voodoo Tactical lifeproof coated firing pin and/or the Wolf primers. I suspect its the firing pin since I was able to get the round to go off once I removed the BCG and cycled the bolt open to close and moved the firing pin. Re-inserted and would fire round. Had this happen with I think 1 CCI primer, but I'm not sure since I was in a rush to shoot off the ammo.
Overall, I am very impressed with the 7mm VAR. I knew that there would be a couple kinks to work out, especially the buffer/gas system relationship. But the round paired with the barrel proved to be a wonderful relationship. I have not had the best experience with Barnes bullets with my other rifle, but glad to see that this will not be the case in this rifle.
So my first trip with the 7mm VAR was pretty productive. My main goal was to collect data for future loading and get a feel for the cartridge. I provided the targets for the hell of it, since some of the ladder tests shot better than my 5.56 AR. So I am really liking the X-Caliber barrel.
Initial impressions on the powders are as follows. LeveReloution : Still need to test more, but so far I like it. 8208 XBR : Its reputation for accuracy was seen pretty early on with the. Even with the ladder test 140 TTSX wasn't terrible. CFE223: This is a powder that should be avoided on barrels longer than 20", although if you have a mild charge on a 20" barrel you could still produce the double pressure spike. Please reference String 11 and notice shot 10 has a double pressure spike that almost mirror each other.
I have attached a chart of Optimal Barrel Times for different barrel lengths. (If you would like the Excel file, let me know.) It will provide reference for the exit time for images Pressure Spike 1 & 2. So in theory you should be ok with a shorter barrel, something I would want to confirm.
Rem 7 1/2(Lot#986) seems to be the goto primer, as CCI 450 & Wolf KVM-223M would produce double pressure spikes. Even though the Muzzle Velocity of CCI 450(Lot#K16U11) & Wolf KVB-223M (Lot#1-10) were slightly better than Rem 7 1/2. Reference String 1-3, these were my primer comparisons. String 4 A & B were actually shot first, to sight in the rifle & initial function check / troubleshooting.
With the rifle I did have some issues, FTE & FTF. The Failure to Extract was from the bolt cycling too fast. I was using a standard Carbine buffer. Forgot to bring my H3 buffer which I think would have solved the issue. Lost 3 brass to cycling issues, necks were too badly damaged for me to salvage. But in most cases the brass was turned around in side the ejection port area, and as my firing went on, the brass would just sit in the ejection port area. Glad I brought my Bob Led Sled, which allowed me to finish the day out at a slower pace. The Failure to Fire could have been 1 of 2 possiblities, the Voodoo Tactical lifeproof coated firing pin and/or the Wolf primers. I suspect its the firing pin since I was able to get the round to go off once I removed the BCG and cycled the bolt open to close and moved the firing pin. Re-inserted and would fire round. Had this happen with I think 1 CCI primer, but I'm not sure since I was in a rush to shoot off the ammo.
Overall, I am very impressed with the 7mm VAR. I knew that there would be a couple kinks to work out, especially the buffer/gas system relationship. But the round paired with the barrel proved to be a wonderful relationship. I have not had the best experience with Barnes bullets with my other rifle, but glad to see that this will not be the case in this rifle.
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