Took my match gun up to Jon Beanland of Beanland Custom Rifles to have my M24 contour Osprey Barrel Works barrel blank fitted. Jon does absolutely 1st class work and having used several ‘smiths over the years, I’m convinced there is no one that does better.
Anyway, Jon had good things to say about the Osprey barrel. Said it was super straight, so much so that there was no need to index the curve, because there just wasn’t any. Also said the groove depth was very uniform. He thought the barrel was a bit harder than most, judging by how many plunges he made with the reemer. He cut the chamber with an Alpha Munitions reemer, and the chamber was a thing of beauty. I had him finish the barrel at 20” for suppressor use.
Loaded a few round of ammo Friday night so I could shoot it yesterday. Used virgin Alpha brass, CCI 450s, H4350, and 88gr ELD-Ms. Loaded five rounds at 33.6gr to zero, and one round each of 34, 34.4, 34.8, 35.2, 35.6, and 36 to try and find max pressure. No case prep on the virgin brass, just deburring and chamfering. Used an RCBS Matchmaster 6mm GT seating die. Runout at the ogive went anywhere from .001” to .006”. I’m not satisfied with anything more than .002” runout, but with virgin brass, it’s not uncommon. I’m confident I’ll get much straighter ammo after I’ve fireformed the brass.
I’m using Magpul AICS patterned magazines and I ran five rounds through to check feeding. Feeding was flawless.
The thing that impressed me the most was how close the first round out of the barrel hit to the zero from the previous barrel (Bartlein 6.5 Creedmoor). Without even a boresight, the first round hit on the left edge of the bullseye, only 1/2 mil from the previous zero. I made an adjustment and shot the next four of the 33.6gr charge. They went into about .6” with 3 of the four being in the .2s. Made another adjustment and shot the last six in the pressure series. They are the ones on the left side of the bullseye. For six rounds with six different powder charges, from 34 to 36gr, I thought this wasn’t too bad. The high shot was the last one, 36gr. Based on how well 34 - 35.6gr grouped, I’m pretty sure I could pick from 34.8 to 35.2gr and run with it. Saw no excess pressure signs from any of the charges. Bolt lift was good, no ejector marks, and primers were nice and round.
Last night, I measured some of the fired brass. When checking runout at the neck, I struggled to see any needle movement on the fired brass, indicating a very concentric chamber. Using a headspace comparator, the brass grew less than .001” on firing. I was able to slide bullets into the necks of the fired brass with my fingers but there was some resistance, indicating it’s a fairly tight necked chamber. I ran a couple of the fired brass through the Matchmaster sizing die with a .249” bushing and bumped the shoulders about .0005”. Runout at the neck on the sized cases was well under .001”.
Finally, I loaded five more rounds from 36.4 to 38gr to continue finding my max charge. Once I determine that, I’ll continue load development in ernest, but I think it’s going to shoot…
John
Anyway, Jon had good things to say about the Osprey barrel. Said it was super straight, so much so that there was no need to index the curve, because there just wasn’t any. Also said the groove depth was very uniform. He thought the barrel was a bit harder than most, judging by how many plunges he made with the reemer. He cut the chamber with an Alpha Munitions reemer, and the chamber was a thing of beauty. I had him finish the barrel at 20” for suppressor use.
Loaded a few round of ammo Friday night so I could shoot it yesterday. Used virgin Alpha brass, CCI 450s, H4350, and 88gr ELD-Ms. Loaded five rounds at 33.6gr to zero, and one round each of 34, 34.4, 34.8, 35.2, 35.6, and 36 to try and find max pressure. No case prep on the virgin brass, just deburring and chamfering. Used an RCBS Matchmaster 6mm GT seating die. Runout at the ogive went anywhere from .001” to .006”. I’m not satisfied with anything more than .002” runout, but with virgin brass, it’s not uncommon. I’m confident I’ll get much straighter ammo after I’ve fireformed the brass.
I’m using Magpul AICS patterned magazines and I ran five rounds through to check feeding. Feeding was flawless.
The thing that impressed me the most was how close the first round out of the barrel hit to the zero from the previous barrel (Bartlein 6.5 Creedmoor). Without even a boresight, the first round hit on the left edge of the bullseye, only 1/2 mil from the previous zero. I made an adjustment and shot the next four of the 33.6gr charge. They went into about .6” with 3 of the four being in the .2s. Made another adjustment and shot the last six in the pressure series. They are the ones on the left side of the bullseye. For six rounds with six different powder charges, from 34 to 36gr, I thought this wasn’t too bad. The high shot was the last one, 36gr. Based on how well 34 - 35.6gr grouped, I’m pretty sure I could pick from 34.8 to 35.2gr and run with it. Saw no excess pressure signs from any of the charges. Bolt lift was good, no ejector marks, and primers were nice and round.
Last night, I measured some of the fired brass. When checking runout at the neck, I struggled to see any needle movement on the fired brass, indicating a very concentric chamber. Using a headspace comparator, the brass grew less than .001” on firing. I was able to slide bullets into the necks of the fired brass with my fingers but there was some resistance, indicating it’s a fairly tight necked chamber. I ran a couple of the fired brass through the Matchmaster sizing die with a .249” bushing and bumped the shoulders about .0005”. Runout at the neck on the sized cases was well under .001”.
Finally, I loaded five more rounds from 36.4 to 38gr to continue finding my max charge. Once I determine that, I’ll continue load development in ernest, but I think it’s going to shoot…
John
