Range Visit 6. No change on sight. Shot both Aguila and CCI. Had two mags with two consecutive malfunctions (FTE) on the second round. The second one I had to dig out of the chamber with a Pointed Stick. Hmmm. Gave up on Aguila and shot rest with CCI. Continued to have zero issues with CCI. Targets included The Test and a mag at 25 yd slow fire. Gonna call it 1” left at 10, and 3” left at 25. Elevation is good, at least. I am going to go ahead and do +6 clicks to move the Groups to the right. It's just how I shoot it, I guess.
Gun is up to 520 rounds now.
So - two FTEs in two magazines with the Aguila, right off the bat. Each time on the second round of the mag. Running through possible causes/answers:
1) Is the ammo to SAAMI specifications?
Checked SAAMI (SAAMI Z299.1 – 2018) for “22LR Sporting”. Cartridge diameter listed as 0.2270. Average diameter of 10 rounds of Aguila was 0.2241. Average of 10 rounds of CCI was 0.2240. Conclusion: Ammo within SAAMI.
2) Does the ammo plunk test in this gun?
After cleaning, did plunk tests with a sample of both ammo. Both Aguila and CCI plunked identically, slithering into the chamber with the same motion. Conclusion: Chamber+Ammo are probably to specification.
3) Noting that both malfunctions today involved FTE, what does the edge of the cartridge look like?
Examining both, the edge of the CCI might be more square than the Aguila, but there is not a lot in it. “Maybe” a better extractor will help.
4) Is it possible the Haloring added enough mass to the bolt, that it is causing the bolt to be slower?
Weighed bolt at 151 grams. Weighed Haloring at 12 grams. Conclusion: Unsure if 8% added to mass of bolt would have an effect. Maybe?
I decided to order an OEM Ruger MKIV Bolt assy with VQ firing pin and extractor off eBay VF store. (Thanks to the eBay link posted by @farscott upthread.) Theory is if I shoot the Aguila with this bolt (no Haloring, VQ extractor/FP) and it still doesn’t work, then I will conclude it’s the ammo and move on.
In other news, I ordered another 500 rounds of CCI.