Leuchtkafer
Member
After getting my feet wet with the CZ factory barrel experiment and PRS build, I felt good to take on this project and start with a fresh blank to fit to a rifle. Not much difference in fitting the barrel vs the CZ, so I don't want to be repetitive with the machining work and we'll skip right to the good stuff. One thing to do when starting with a blank is to evaluate it before doing any work to it. I want to get a feel for the quality and consistency of the bore, and identify which direction the taper goes if it's been taper lapped, so I know which end will be the muzzle and which will be the chamber. If there's any inconsistency in the bore diameter at the muzzle end, some extra care would have to be taken to ensure a tight spot is accurately identified and marked to be cut and crowned there. This blank slugged well and I could put the crown anywhere I wanted. Straight 0.850" diameter finished at 24.5".
At the range, I noted a number of issues with RWS ammo. There was a ton of fail-to-fire, with Rifle Match being completely unusable. With the Target Rifle orange box, some rounds would be difficult to start into the chamber, others would start but jam up on the casing. Less chambering issues with Special Match and R-100, though it seems to me the spec on RWS ammo dimensions is a hair too big for this chamber. Results with all RWS were poor, to the point of me questioning everything I thought I knew and thinking about selling my lathe and giving up on it all. I tossed the targets in the trash. Then I gave SK and Lapua ammo a try, and had to laugh at God's sense of humour. I've never experienced it before that a rifle just wouldn't shoot any ammo from a particular brand. It's always been if the barrel is good, tuned, and the ammo is good, the results are good, no matter the brand. That's 3 barrels I've done with this chamber now and all of them don't do well with RWS.
I couldn't make any progress testing the tuner with the RWS ammo, so I set it to 2-60 and left it there for all the SK and Lapua groups. I don't see anything of concern here or unusual for rimfire. Results are in line with expectations and typical of the average ammo you get buying a random lot of whatever is available. POI between the ammo types is stable, the Long Range runs faster so a higher POI is expected. Some vertical in the groupings suggests to me that while I'm in the ballpark for the tuner setting, a few more range days to refine it are required. This barrel profile plus a Harrells tuner are practically made for each other, and the setting barrel to barrel should be close. If you ascribe to Positive Compensation, disregard and carry on with your pursuit.
There's never a free lunch in rimfire accuracy, you get out of it what you put into it. I'm satisfied with this result for a freshly machined barrel, in the cold, with random ammo, and a tuner that still needs testing work. People like to show off their best results, rather than showing everything they went through to get there. I'm not going to crop one of the 0.1's groups and boast about how awesome my rifle is, that would be dishonest. There's so much more to producing those tiny groups than slapping on a custom barrel and going shooting. Fitting a good barrel is only the beginning, and I look forward to seeing what I can achieve with this, in the warmer weather of course
At the range, I noted a number of issues with RWS ammo. There was a ton of fail-to-fire, with Rifle Match being completely unusable. With the Target Rifle orange box, some rounds would be difficult to start into the chamber, others would start but jam up on the casing. Less chambering issues with Special Match and R-100, though it seems to me the spec on RWS ammo dimensions is a hair too big for this chamber. Results with all RWS were poor, to the point of me questioning everything I thought I knew and thinking about selling my lathe and giving up on it all. I tossed the targets in the trash. Then I gave SK and Lapua ammo a try, and had to laugh at God's sense of humour. I've never experienced it before that a rifle just wouldn't shoot any ammo from a particular brand. It's always been if the barrel is good, tuned, and the ammo is good, the results are good, no matter the brand. That's 3 barrels I've done with this chamber now and all of them don't do well with RWS.
I couldn't make any progress testing the tuner with the RWS ammo, so I set it to 2-60 and left it there for all the SK and Lapua groups. I don't see anything of concern here or unusual for rimfire. Results are in line with expectations and typical of the average ammo you get buying a random lot of whatever is available. POI between the ammo types is stable, the Long Range runs faster so a higher POI is expected. Some vertical in the groupings suggests to me that while I'm in the ballpark for the tuner setting, a few more range days to refine it are required. This barrel profile plus a Harrells tuner are practically made for each other, and the setting barrel to barrel should be close. If you ascribe to Positive Compensation, disregard and carry on with your pursuit.
There's never a free lunch in rimfire accuracy, you get out of it what you put into it. I'm satisfied with this result for a freshly machined barrel, in the cold, with random ammo, and a tuner that still needs testing work. People like to show off their best results, rather than showing everything they went through to get there. I'm not going to crop one of the 0.1's groups and boast about how awesome my rifle is, that would be dishonest. There's so much more to producing those tiny groups than slapping on a custom barrel and going shooting. Fitting a good barrel is only the beginning, and I look forward to seeing what I can achieve with this, in the warmer weather of course
