IMR 4451 What Cartridges Are You Using It For?

I shoot it with 147 ELD's in 6.5CM need to bring it down a node, it's a little hot (getting ejector marks) but is still safe to run......not overly concerned about brass and enjoying 2858 fps (not a typo) verified with a magneeto speed. It groups well and has single digit SD's.
 
I shot it initially in 6.5 Creedmoor - couldn't find H4350 when I started loading for it. I have a load for my first barrel using 4451 and 140 RDFs that shoots sub-half-MOA. For me, 4451 was slower than H4350. I'm not getting any pressure signs, but start getting heavy bolt lift if things get wet - and I'm still about 80 fps shy of what I can do with H4350 in that barrel. So, I switched to H4350 when I could.
 
Tried it in 6.5c, had issues with hang fires but that may be more the fault of the small flash hole brass/weak primers. Groups were good given what was going on, I'll try it again with a better primer when I can get back to the range.
 
I've been shooting it in 6.5 CM for the last two years with great results. My load in Hornady cases is 41.8 gr. IMR 4451, CCI BR2 primer, Hornady 140 ELDM bullet. Through my 24" Bartleins it gives about 2725 fps with wonderful accuracy. My load for H4350 is 42.5 grs. with the same other components and will yield about 25 fps faster. My IMR 4451 load shoots just as accurately as my H4350 load.
 
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I found I needed half a grain more of 4451 to match the speed of a H4350 charge but I was able to get a higher speed before pressure than H4350 In my 260.
42.5 with a 140 ELDM was a low node but I’d immediately use that load If I wanted tiny groups.
It hammered consistently with a speed of 2715.

My charge that a burned the majority of my 4451 with was pushing 147’s at 2800 that was totally GTG even in the 90’s with pressure showing up at about 2880 and great vertical even a bit past a mile.
In fact that load is what I broke my mile cherry with.
 
Agree with M1 and Steel - nearly identical results in my 24" Bartlein 6.5CM. Accuracy was a bit better but speed was down 25-30 fps. Once I got H4350 again; I quit playing with it, but I might try it again. The H4350 gets me in the .25" area pretty regularly but I saw several .1's with the slightly slower 4451 loads. Matching that slower velocity with H4350 was terrible - go figure. 4451 was quite a bit dirtier - maybe that CFE technology lays down so much sh!t that no copper will stick to it...
 
Tried it in 6.5c, had issues with hang fires but that may be more the fault of the small flash hole brass/weak primers. Groups were good given what was going on, I'll try it again with a better primer when I can get back to the range.

I used it in Lapua brass without issue - using CCI 450 (small rifle magnum), BR4, and Federal 205M primers.
 
Thats good to hear that the 450’s are working with it. That is what I’ve loaded the second test batch with. I’m using Peterson instead of Lapua, but same flash hole. Hopefully it will work out.
 
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I’m getting good results from my 6.5 creed 26” factory 700 varmit. 42.1 gr. At 2750 FPS and 5 standard deviation. No pressure at all but I’m happy where I’m at.
Sounds similar to mine but mine is a 26 inch 6.5cm Criterion barrel and using 42.7 grains I'm at 2858fps with 147's but getting some pressure signs. I don't shoot a ton right know so I'm fine with being a little hard on the brass.
 
I used it in 6.5CM and I had some good 100yd groups. My book shows max FPS was 2687, there are no notes regarding swipes or heavy bolt lift. Alpha Munitions brass - LRP Fed 210M - 143 ELDX - 40.8 to 41.5 grains.

I did not mess with it much because I found RL26
 
6.5 Creedmoor
4451 in Nebraska is a good choice as the temps here can vary literally by 130 degrees throughout the year.
40.9-41.1 gns w 140 gn ELDX, Lapua small primer brass. Federal 205M primers
 
260 Rem.
Loading 43.2 gr with the 140 gr SMK and CCI200 I'm my suppressed 20" Tikka CTR. 1/2 MOA at 2710 fos.
i have the same rifle. but using Federal 210 primers and i am getting the same speed but using 42.3 grains of 4451
excellent powder...i ordered the bigger jug my last actual powder shipped purchase from PV