I don’t know if anyone wants this, but I spent a lot of time thinking on it and decided to write it up.
I wanted to compare bullet options across the 22 Creedmoor, 6 Creedmoor, and 6UM for my preference for a 16 inch barrel. Categories that interested me were range at 1800 fps, wind number, recoil, and danger zone. I found the concept of recoil efficiency from solarshooter really interesting, and I included his awesome chart.
To start, I pulled the book max for each round with the expected velocity from a 24 inch barrel. I subtracted 30 per inch for the estimation for a 16 inch barrel. I then combed through rokslide looking for load data for 16 inch barrels with measured MV.
I ran ballistic calculators off the loads I found on rokslide rather than the ideal from book max as it seemed the actual speeds were generally lower (especially in the 22CM). I first did this in Hornady 4DOF at 5000 feet. I then did JBM Calculator which also provided danger space on a 10 inch target at 500 yards.
The results were drastically different making me think I did something wrong in JBM, and I’d love to see if someone can pick up my mistake. If nothing else, the results were proportional throughout the calibers, so still useful as a comparison.
Finally, I ran recoil numbers using an 8lb gun and charge weights based on what I found on rokslide.
I’m intrigued by the concept of the 22UM so I included the possibilities if Form gets close to his goal of 3500fps from a 20 inch barrel.
I started this expecting to see that the 88 ELDM from a 22 creedmoor would provide the optimal combination, but I was somewhat surprised to see that the 95TMK from a 6 creedmoor had a very slight increase in recoil with the same wind number and (depending on calculator) a better terminal range. I may even be underestimating the 95 TMK’s capabilities given that someone reported 3137 out of an 18 inch barrel which could mean that 3050fps+ is even possible. It was the only bullet where I found reports of an increase over book max - 240fps.
This mainly came down to the difference between book ideal and actual results with a 16 inch 22 creedmoor for the 88 ELDM. I included mwoolsey5’s chart on powders and pressures for 16 inch barrels in a 22 creedmoor which was another source I leaned on. I assume a cartridge this overbore suffers more as length decreases. This seems to apply to the 6UM as well.
I’m curious if anyone has seen better results than I found with a 16 inch 22CM. Otherwise, my conclusion would be to say that the 95TMK in a 6 creedmoor is ideal for 0-600yd hunting in a 16 inch barrel.
The 22UM feels like the Holy Grail if it even comes close to the goal. That said, with how much the 22CM seems to suffers from decrease in length, I would guess that the 22UM would be even more dramatic.
Final caveat: I’ve read a whole lot more than I’ve shot or reloaded. This is almost entirely theoretical. Any of these weapon systems would outperform my abilities. I’m hoping at the S2HU course this summer, I can start to bring my capability a little closer to taking advantage of any of this.
many times.
