I'm working on fine tuning a load for a Remington ADL .243 with a 24" barrel. I'm using Winchester brass, H4350 and a CCI 200. What have you found to be your pet load with this combination? I've seen everything from 40-42 gr. After working up to it, it looks like my load is going to be in the neighborhood of 41.8 gr. I realize this is over book max a considerable amount. However, I landed on this same charge with a Nosler 95 BT and it is giving me 2936 fps.

H4350 is really not a good powder for the 243 and 95gr. I’ve used it but the results are not great. You really need something in the RL25 burn rate area.

For a 100 grain Speer or Sierra, I've loaded 38 grains of 4064, for like forever... in the 243.

its always been fast and accurate... in the 2900 fps range...

This is the first time I've ever heard H4350 isn't recommended for 95 gr bullets in .243. I have some H1000 I could try but always had good results with IMR4350 in the past.

Don’t get me wrong, 4350 will work but you’re going to give up a couple hundred fps easy. I run 42 gr H4350 behind 95 gr partitions in my loaner 243, it’s 2750 fps and 1.25” groups. I run that load because I had lots of H4350 and found some partion seconds cheap, and it’s a $200 rifle I bought for my dad to shoot deer at under 200 yds with. It works but It really capable of running 3000+ fps. H1000 might be worth a look, my books all list powders around 4350 burn rates as pretty slow. Magnum and RL 25 are listed as the fastest for what it’s worth.

I can't think of any cartridge I've used H 1000 in that didn't work well for both accuracy and velocity...

experimenting with RL 26 when it came out, starting with the 243, also gave excellent results....

I enjoy playing around with the 243s, but when its hunting time.... I always just go back to the above mentioned standby 4064 load.... kinda like throwing 10w30 in your car engine.. seems to work well regardless.

doesn't mean I don't experiment a lot with it anyway... and Speer bullets are cheap...

Devnull I think you are running on the hot side you are getting about 100 fps more than the Nosler data and almost 2 grains over max. Could be fine but I would measure the case expansion and also reload the same case 10-12 times to see about primer pocket expansion. But more likely I would back down to 38-39 grains and if I wanted more velocity I would switch to R17, R16, R26, R22, MRP, R25, Magnum, or H1000. All of these will run in the 2900 to 3100+ range with safe book loads.

I have been using 42.5 of H4350 / 100 gr Sierra Pro Hunter in my .243 .Getting 3/4 " groups at 100. About 2900 fps . The Pro hunter Flat base, shoots better in mine than the BT and likes to be seated deeper.

Unless shooting longer distances, pushing those 95 or 100gr Speer or Sierra past 2900 don't hold up well

According to Hodgdon data with the 100-grain bullet the OP was asking about, you gain 27 fps with H-1000 versus H4350. Just how will the OP know his pressures are okay by “measuring the case expansion”? That has as much to do with chamber dimensions as it does pressures.


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I always had best results with 42.5-43.5 grs. H 4831 with 90 - 100 Sierra, Nosler, Hornady and Speer. As stated above, I would really be looking at a slower powder.

I am shooting 41 grains of h 4350 and 105 gr hybrids. 3000 fps. No pressure issues. Your 100 gr bullets would probably be just fine. I also use 41 gr of h 4350 with 95 gr nosler ballistic tips in my boys tikka 243. It works very well.

41gr RL-17 under a 100gr partition runs 3050 fps in my old pre-64 FWT 243 with a 22" barrel, shot my biggest doe with that setup a couple years ago at 55 yards, straight thru both shoulders, DRT, she had to weigh near 180lbs on the hoof, old grey heifer she was, ate really good though.

Hybrid 100v also works well with those Speers in the 243.

I use IMR4350 and H414 in my 243s with 95gr NBTs. Accuracy has always been excellent, and speed is fast enough...

FWIW in the same rifle your using I had the best accuracy with RL26 and 100 grain bullets.