DoneNOut
Well-Known Member
There was a post made in regards to "Just two rifles". That got me thinking, and I suggested 243 WIN as the lighter end rifle. Tried to capture as many aspects into that choice. 243 can cover varmint to deer sized game, and it can reach out long range for zombies. Look at the success the 6mm cartridges are having at 1000yds and more. Well, I recommended a 243 without having one, so I had to remedy that "talking out my butt".
I couldn't make it that easy on myself though. If I only had two rifles to load for I would probably get bored and thus the Ackley Improved aspect came to mind. So, I got a 243AI. When I got it set up and got all the components in, I was in reloader's heaven. I "Rainmaned" out on the cartridge and these are lessons learned:
- 243AI chamber still shoots standard 243 WIN ammo really daggum great! Bug holes. No problems with chambering either. I wouldn't even know I had an AI version. So, in the Apocalypse(s) I can find and shoot 243 WIN ammo I find in the abandoned gun stores, full of guns, ammo, & supplies.
- With the AI chamber you get two guns in one! Every time I fire in 243 WIN mode, "Look, there's more!" I am making another case for the AI! For instance, I am cruising 88gr Hammers 3400fps 243 mode, 105 Berger VLDT 3150fps, and then I 115 VLDT for the same 3150fps in AI mode. Why not? 10 grains more bullet at same velocity? Total WIN in my books. (26" barrel)
- Got to tread carefully on the AI side of things though. I've not had a cartridge spike so fast to high pressure. It isn't like my typical load development where I was used to seeing some indicators to back off. With this AI it was "all is good, little more powder, oh schit!" .5gr increments are too big a jump for this AI cartridge business. I cratered out my bolt face something fierce...This is an Aero Precision SOLUS bolt, so thankfully they have bolt heads for replacement.
- RL17 took the 1st place versatility spot across the board. It is the "Easy Powder Button" here.
Using Lapua brass and WLR primers, 2.880 COL, .006" jump loaded, but upon firing will be touching lands:
@ 30F. 750 ft ELE
RL17
88 HH - 45gr 3420fps
105 VLDT - 42.5gr 3150fps
I made an executive decision to run the AI mode with only 115gr VLDT. Reasons are to save "some" barrel & simplify the reloading "a bit". I also think the extra case space of AI is better met with a heavier bullet!
243 AI with RL17:
115 VLDT
43.5gr @ soon to be tested. (I expect 3180s)
44gr produced 3225fps, but is at danger zone of over pressure. 55F temp test conditions. 75 F. probably over pressure.
44.5gr over pressure. Pierced primer/ejector smear Not much more velocity @ 3257fps.
I read on the multiple forums guys using SLOW powder like RL26, H1000, Retumbo even. Well, had to test that out too. I found N170 & N570 to be champs! They have both been sitting in the armory for years waiting for an opportunity like this! Both shooting bug holes!
115 VLDT AI:
N170- 50gr @ 3150fps, 13 SD. Powder fill just under the neck. Perfect.
N570 - 50gr @3150fps 9 SD. Powder is filled to the neck. Some vibration of the press lever is needed to prevent crunching kernels when bullet seating. Those kernels are the size of Tic-Tacs too! So lots of air gaps get filled upon bullet seating. My seating depths are spot on since there is compressed powder. I don't think I will need to worry too much about over pressure with hotter ambient temps considering how slow these powders are, I might be utilizing the mechanical way of limiting over pressure. I will find out.
I couldn't make it that easy on myself though. If I only had two rifles to load for I would probably get bored and thus the Ackley Improved aspect came to mind. So, I got a 243AI. When I got it set up and got all the components in, I was in reloader's heaven. I "Rainmaned" out on the cartridge and these are lessons learned:
- 243AI chamber still shoots standard 243 WIN ammo really daggum great! Bug holes. No problems with chambering either. I wouldn't even know I had an AI version. So, in the Apocalypse(s) I can find and shoot 243 WIN ammo I find in the abandoned gun stores, full of guns, ammo, & supplies.
- With the AI chamber you get two guns in one! Every time I fire in 243 WIN mode, "Look, there's more!" I am making another case for the AI! For instance, I am cruising 88gr Hammers 3400fps 243 mode, 105 Berger VLDT 3150fps, and then I 115 VLDT for the same 3150fps in AI mode. Why not? 10 grains more bullet at same velocity? Total WIN in my books. (26" barrel)
- Got to tread carefully on the AI side of things though. I've not had a cartridge spike so fast to high pressure. It isn't like my typical load development where I was used to seeing some indicators to back off. With this AI it was "all is good, little more powder, oh schit!" .5gr increments are too big a jump for this AI cartridge business. I cratered out my bolt face something fierce...This is an Aero Precision SOLUS bolt, so thankfully they have bolt heads for replacement.
- RL17 took the 1st place versatility spot across the board. It is the "Easy Powder Button" here.
Using Lapua brass and WLR primers, 2.880 COL, .006" jump loaded, but upon firing will be touching lands:
@ 30F. 750 ft ELE
RL17
88 HH - 45gr 3420fps
105 VLDT - 42.5gr 3150fps
I made an executive decision to run the AI mode with only 115gr VLDT. Reasons are to save "some" barrel & simplify the reloading "a bit". I also think the extra case space of AI is better met with a heavier bullet!
243 AI with RL17:
115 VLDT
43.5gr @ soon to be tested. (I expect 3180s)
44gr produced 3225fps, but is at danger zone of over pressure. 55F temp test conditions. 75 F. probably over pressure.
44.5gr over pressure. Pierced primer/ejector smear Not much more velocity @ 3257fps.
I read on the multiple forums guys using SLOW powder like RL26, H1000, Retumbo even. Well, had to test that out too. I found N170 & N570 to be champs! They have both been sitting in the armory for years waiting for an opportunity like this! Both shooting bug holes!
115 VLDT AI:
N170- 50gr @ 3150fps, 13 SD. Powder fill just under the neck. Perfect.
N570 - 50gr @3150fps 9 SD. Powder is filled to the neck. Some vibration of the press lever is needed to prevent crunching kernels when bullet seating. Those kernels are the size of Tic-Tacs too! So lots of air gaps get filled upon bullet seating. My seating depths are spot on since there is compressed powder. I don't think I will need to worry too much about over pressure with hotter ambient temps considering how slow these powders are, I might be utilizing the mechanical way of limiting over pressure. I will find out.
Last edited:
memtb
memtb
