190gr ABLR over IMR 4320, can it be done?

[McSnipsy291]

Hey just thought I would probe those here who may have experience with shooting heavies in .308 on the load I have patched together for a 19" AR-10 running rifle gas.

Fiocci Brass
190gr Nosler ABLR
Fed 210 primer
43.0gr IMR 4320
2.810" OACL

I couldn't find much info on 4320, especially with heavier bullets but did find some load data for 180 and 200gr AB, 208gr amax, and 185gr Berger's, and kind of had to extrapolate a load from that. Hopefully those of you with some experience can drop some wisdom as to the likelihood of this working. If the internet can be trusted 4320 may be a hidden jewel left over from a simpler time.

And just so this doesn't turn into a bullet weight brawl I know 168s can be driven a lot faster and have plenty of BC to carry that speed and energy a long way so this may not be my forever load. I am mostly just probing to see if I am near the beaten path or if I've lost my mind and gone on a misguided adventure to kaboom town. I know 190 is on the heavy side for .308 and I may switch to the new 168gr down the road but I have always been a fan of heavy bullets and already have 300 of the 190s and some 4320 around so I figured I might as well use them up until I can afford to explore further.. if they work well I will just keep rolling with them.. if they just fall short (literally) I will look at something lighter down the road.

 

[AMGtuned]

I ran some 4320 with Nosler 150 ballistic tip through a couple of my .308 rifles. The exact charge was 45gr. In my AR10, I got crazy pressure signs. In my 700 tactical, they shot lights out at about 2750fps. It was one of those moments I wish I had thought through more. Had components on hand, loaded them all identical, and headed out. Like I said, bolt gun loves em; work up with a gas gun. 45gr was way too much in my AR10. 42gr of Varget got me to 2600 with a 168

 

[McSnipsy291]

Went out and test fired it. Didn't blow up in my face but flattened the primers out pretty good and got an ejector swipe. Plus I was off the node and it didn't group. Going to try backing the next bunch down to 41gr and 42gr and see if either one groups any better. If that doesn't work I will probably just be switching to varget like everyone else.

 

[918v]

That’s a good plan. You were 1-2 grains over max in that heavy brass.

 

[McSnipsy291]

After two more trips out and a bunch more tinkering I've figured out that for most the brass I have 41gr is what I would consider my max load and I finally got it to shoot decent at 39gr (groups still suck due to me being a lousy shot) but they are at least going where the gun happens to be pointed when a shot breaks.