Home Forums Hunting & Shooting Ask The Gunwriters 280AI and H4350

Anybody use H4350 in the 280AI with 140 grain bullets, especially the Barnes TTSX? Surprisingly little data available for this combo.

Thanks.

I'm not 100% sure, but I'm loading 56.0 or 56.5 grains of imr4350 under a 140 ttsx.
Chrono read, 3150 fps. Not screaming, but I've killed 2 cow elk, and 2 Oryx with this load.

Never really worked for me. IMR 4831, RL-19 and occasionally RL-22 were my huckleberries. I used 140’s for years but settled on 150’s as the best for my applications. Tried 168’s for a couple of years and didn’t care for the rainbow trajectory.

I’ve shot a 280AI for going on 35 years now. Jarrett.

Barnes has data for IMR 4350 and the 140 grain TTSX, and H 4350 is very close in burn rate. Use the starting load with IMR 4350 and go from there. Hodgdon has load data for the 150 grain TTSX and H 4350.

IMR 4350 is often noted as being the most accurate powder in both the 280 and 280 Ackley. Since H 4350 is nearly the same, I would expect excellent results with it. I have a lot of IMR 4350 and will be using it in my 280 Ackley.

Agree. Jarrett tunes each rifle they send out. I noticed a good number of rifles showed their best groups with IMR4350....none of mine have though. Had one of mine rebarreled as I had shot the first barrel out. The next barrel was one of their own barrels and it adored RL15 of all things.

Jarrett uses VV165 as his accuracy load for the 280 AI, I am thinking at 62.5 grains but cross reference this before blowing up your rifle due to my poor memory.

H4350 used to be right after H4831 in the 270 so should be good in the 280 too.

Fixed it 62,5 to maximum 63.5.

DBoston,

I doubt you could get 72.5 N165 in a .280 AI case.

Plus, Vihtavuori listed 68.5 grains as maximum with the 160 Speer Grand Slam--in the 7mm Remington Magnum.

Do what?

Thanks, guys.

I've loaded and shot 56-59 grains of H4350. Hodgdon shows 55.5 as max, but my Kimber Montana does not exhibit any of the classic pressure signs at 59 grains. Accuracy certainly improved with increasing load.

Sorry was thinking of my 257 Weatherby loads with MRP.

"Classic pressure signs" often don't show up until you are way, way above maximum. Meanwhile, your gun is getting pounded, and nothing about that is good.

I have loaded 59.0 grains of H-4350 in my 280 AI with the 140 gr. Sierra Pro Hunter for years. This load was developed for my rifle by Jarrett Rifles. I would not start with that load in any other rifle without carefully working up while watching for pressure signs. All rifles are different. I use Fed 215 primers.

I’m using H4350 in my 280AI with 150TTSX. shoots tiny groups. Don’t have exact data in front of me though.

Been using the 280 AI long before they were in reloading manuals..

In two different rifles H-4831sc/ H-4831 gives the best performance, be it 140 or 150 partitions it shoots less than .5" without issue... The hunting rifle is a MRC x3 extreme and the target rifle is built on a Remington action with a 25" #3 PAC-Nor match stainless..

With the Ackley be very careful because they just don't show pressure sign's like non-Ackley rounds ...

You can push them to 3250 with 140's but 3100 fps seems to be the sweet spot and 2925 fps with 150's... The 168 Match -best node is 2810 fps which will hammer 18" steel out to 1200 yards...

Cooper Creek loads some fine ammo for the Ackley, which I have tested in my rifles for a non reloading hunting partner that owns an Ackley - highly recommended if you need the 280 AI stamped on the brass...

Personally; I fire form Norma which is my preferred for the Ackley..

Have fun and enjoy the best dang shooting stick made- in my opinion the 150 Partition placed in the shoulder will drop anything you shoot..

Don't shoot your eye out..