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Imr 4451?

jack simpson

Sergeant
Full Member
Minuteman
Apr 11, 2011
141
0
63
Kentucky
Have not been able to put my hands on any H 4350 for months. The local gun store just got some IMR 4451 in. I will be loading for 6.5 Creedmoor. Just been looking for someone who has had any experience with this powder and cal. in 140'ish projectile. Thanks
 
It works very well. A good replacement for H4350. Not quite as temp insensitive but still better than others.
 
Still in load development but like it so far. Thinking I will end up around 41.5gr with 140's. Hoping to get out this week and finish up testing.
 
I use it in 6.5 Creed and don't worry about H4350 anymore. This stuff works just as good.
 
42.1 grains behind Hornady 140 gr. BTHP Match. Works great. But just the same I'm going to try Reloder 16 tomorrow.
 
IMR4451 is a very good powder for the 6.5 Creedmoor. As stated above not quite as stable in temp swings as H4350 but very respectable. Another, I think, better alternative for H4350 is Alliant RL16. I've been seeing some very low single-digit SDs, great temp stability and excellent accuracy with it so far. I just loaded some test rounds in 6.5 Creedmoor using RL16, 140 ELD-M, Lapua 6.5CM brass and CCI 450 primers.
 
Works great

Finally got my load worked up with IMR 4451 with the last remaining 140 Amax's I had in my 6.5cm...heres the final numbers as collected from my magneetospeed

Max = 2873
Min = 2859
AVG= 2868
ES = 14
SD = 5.8

Shot 0.3-0.4 moa seated 0.020 off lands ( and this was horizontal spread due to me being a little rusty and being at a local range with .30-06 And literal BAR machine guns blasting on each side of me)
 
Works great

Finally got my load worked up with IMR 4451 with the last remaining 140 Amax's I had in my 6.5cm...heres the final numbers as collected from my magneetospeed

Max = 2873
Min = 2859
AVG= 2868
ES = 14
SD = 5.8

Shot 0.3-0.4 moa seated 0.020 off lands ( and this was horizontal spread due to me being a little rusty and being at a local range with .30-06 And literal BAR machine guns blasting on each side of me)

How many grains did you end up using?
 
42.7 grains, as always know your rifle/chamber and edge up slowly while collecting data and inspecting brass
 
42.7 grains, as always know your rifle/chamber and edge up slowly while collecting data and inspecting brass
definitely! I have alread done 41-42 and have loads up to 42.7 already loaded in .2 grain increments to try. Was just curious where you ended up. Thanks

 
In 6.5x47, 41 grains of H4350 and 130 VLD's was giving me 2834 ft/sec.

I did complete load work up of IMR 4451, from 40 to 42.5 grains and the best combination of accuracy and low sd's was at 41.2 grains and 2838 ft/sec
 
42.4 of 4451 treats me quite well under the 140 ELD-M. Plus, I'm right at about 2750 at 10 feet off the muzzle.
 
If you already have a H4350 load, load the exact same with 4451 and all it good. It will be 10-15 fps faster in most cases.
 
Working up loads with 4451 , but what can I expect from 20 in barrel. Already ran 41.5 at 100 with less than half inch spread? Not sure if it has enough gas to go 1k
 
Ran the rest of my load test with RPR 24' barrel, 140 gr Hornady Match BTHP, Hornady brass and CCI primers. Seated .020 off lands and sweet spot came in at 42 gr of 4451. I am going to mess with seating depth next. Velocity was only 2630 fps average measured with a Magnetospeed. Even at 42.7gr on my tests, I was still not over 2700 fps.
 
Even at 42.7gr on my tests, I was still not over 2700 fps.

I'm seeing similar things (24" Bartlein barrel on my gun, Hornady brass, CCI 200 primer, Nosler 140gr RDF) - at 42.9, I'm right at 2700. I'm wondering if perhaps I've got a slow lot. Will be summarizing data tomorrow and writing up. Today, I ran heavier loads, and reached 2800 - just starting to flatten and crater primers, at that point, but no change in bolt lift and no ejector marks on the case head. Kind of surprising - I figured I'd end up pulling some of those.

 
I'm seeing similar things (24" Bartlein barrel on my gun, Hornady brass, CCI 200 primer, Nosler 140gr RDF) - at 42.9, I'm right at 2700. I'm wondering if perhaps I've got a slow lot. Will be summarizing data tomorrow and writing up. Today, I ran heavier loads, and reached 2800 - just starting to flatten and crater primers, at that point, but no change in bolt lift and no ejector marks on the case head. Kind of surprising - I figured I'd end up pulling some of those.

I'm running a 23.75" barrel using prime brass, s&b primers, and the 140 rdf, 4451 at 42.6 grains and was at 2740 fps before a carbon ring and then it speed up to 2845. I've shot 3-4 different lots of 4451 and never had an issue with it being slow. It is a little temp sensitive, but that would be the only thing I could think of that would keep it that slow.
 
It is a little temp sensitive, but that would be the only thing I could think of that would keep it that slow.

A week ago, it was 73.6 degrees here. I chrono'ed 42.9 at 2710. Today, it was 58.3 degrees, and I chrono'ed 42.9 at 2702. Last week, 42.3 was 2691, while this week it was 2650. Don't know what your temps are like.

It's occurred to me that I might have a carbon ring going on - going to look at that - but Hornady 140gr ELD-M factory stuff has been pretty consistent since the barrel was new, ranging between 2662 with a mere 25 rounds on the barrel (at 60.1 degrees) to 2700 last week with 225 rounds on the barrel at 73.6 degrees, to 2700 again today at 58.3 degrees with 300-ish on the barrel. The barrel seems to have sped up slightly, but other than that...??? Still, I'm going to look at being certain I don't have anything weird happening in the throat.

 
If you already have a H4350 load, load the exact same with 4451 and all it good. It will be 10-15 fps faster in most cases.

I think diff lots have a little to do with what you are saying, 2 yrs ago I would have agreed with you 100%, todays lots of 4451 we are seeing around here seem to give up speed to H4350.
 
A week ago, it was 73.6 degrees here. I chrono'ed 42.9 at 2710. Today, it was 58.3 degrees, and I chrono'ed 42.9 at 2702. Last week, 42.3 was 2691, while this week it was 2650. Don't know what your temps are like.

It's occurred to me that I might have a carbon ring going on - going to look at that - but Hornady 140gr ELD-M factory stuff has been pretty consistent since the barrel was new, ranging between 2662 with a mere 25 rounds on the barrel (at 60.1 degrees) to 2700 last week with 225 rounds on the barrel at 73.6 degrees, to 2700 again today at 58.3 degrees with 300-ish on the barrel. The barrel seems to have sped up slightly, but other than that...??? Still, I'm going to look at being certain I don't have anything weird happening in the throat.

Carbon ring will cause an increase in pressure and thus an increase in velocity. Idk whats up with your velocity. thats weird. i've got 150 fps on ya with .3 grains less powder and a slightly shorter barrel.
 
1941USMC,

I'm loading 43.0 gr. of 4451 with Lapua 139 gr. Scenars and getting 2730 fps from a 20"barrel. Keep in mind this is MY rifle and it may not be safe in yours.
 
I found a nice node with 42.8 gn of IMR-4451 behind a 140 RDF in my 260. Winchester 243 Brass, CCI 200 primer.

KMW 260
24" Krieger

I chronographed 42.0 & 43.0 on the magnetospeed
42.0 - 2728 fps
43.0 - 2748 fps

I will test at long range to see how it holds up.. Expect it will clock 2730 with the 42.8

 
I'll start loading for the first time for the 260 rem with 147gr ELD Match and IMR 4451.
What should my starting load be?
Also, any ideas on the OAL? I'll have the components before the barrel. Should I wait to get the barrel to measure the max OAL first? Or it's like a 308, where you can do a 2.8" OAL and be pretty sure it will fit any barrel. I'm thinking those bullet are going to be pretty long and it's better to wait and get the barrel first.
 
I'll start loading for the first time for the 260 rem with 147gr ELD Match and IMR 4451.
What should my starting load be?
Also, any ideas on the OAL? I'll have the components before the barrel. Should I wait to get the barrel to measure the max OAL first? Or it's like a 308, where you can do a 2.8" OAL and be pretty sure it will fit any barrel. I'm thinking those bullet are going to be pretty long and it's better to wait and get the barrel first.


I would wait until you get your barrel to set OAL. With that said, I always start OFF the lands with load development.. Also, I have found the Hornady ELD to be very jump tolerant.

As as for what your starting load shall be, always start with published data and work up. Even the slightest difference in chamber dimensions can make pressure signs at lower charges..

It seems like 4451 will be a good powder, but I'll need to chrono further and test at long range..

Be safe and keep us posted on your results..
 
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Anyone have a load using 4451 or RL 16 using 147gr ELD? I have Superformance powder, but I'm not finding any load info beside the one from Hornady.
 
aubie515 - I have a load I'm in the middle of developing, but I'm away from my notes for about a week, so I can't give you exact details. The basics are... 24" Bartlein barrel, Lapua virgin brass, CCI 450 primer. I'm loading around 43.5gr 4451 with the 147, seated .020 off the lands, and it's making about 2750 fps in my tube. My barrel seems to be a tad slower than what most folks report, but with a 140gr bullet, it lines up perfectly with the Sierra 142 SMK data for 4451. Obviously, that's my data in my gun, and YMMV will definitely vary. I'll try to update this post when I get back home next week - shoot me a PM if I forget ;-)