09-11-2018, 09:26 PM
I do have real world numbers.
I had two Grendel barrels made for me by my barrel maker. He used the same reamer, same lot of steel, same groove diameter, etc. You will not get closer to the same barrel but one is a 20 inch and one a 26 inch.
I chronographed many loads from each but the one load I use the most is 30 grains of 2520, Lapua Brass, CCI-450 primer, and a 120 grain Match King.
20" velocity is 2438 fps.
26" velocity is 2551 fps.
Average velocity increase per inch of barrel length is 18.8 fps.
LR55
I had two Grendel barrels made for me by my barrel maker. He used the same reamer, same lot of steel, same groove diameter, etc. You will not get closer to the same barrel but one is a 20 inch and one a 26 inch.
I chronographed many loads from each but the one load I use the most is 30 grains of 2520, Lapua Brass, CCI-450 primer, and a 120 grain Match King.
20" velocity is 2438 fps.
26" velocity is 2551 fps.
Average velocity increase per inch of barrel length is 18.8 fps.
LR55