what is real world feedback on IMR4451?

From the company writeups it sounds like something quite similar to Reloder-17 with an additional benefit of reducing copper fouling.

Is the velocity advantage real? Is the pressure truly low and extended?

I am interested in trying this out in 243Win, maybe even with a 69gn GSC bullet in a 20" barrel. Yes, that would break all of the 'rules of thumb'. Also of interest would be the 375Ruger with light and medium weight bullets and with a 416Rigby and the 330GSC HV.

It will be several months before I will have an opportunity to test these, so I have time to order some 4451 if the feedback is positive.

If you mean 4461 it's about the same loading as Hodgdon 4895. .308 load data is almost identical between the two. You can check other cartridge loadings via the Hodgdon website.

There is no 4461.
IMR 4166™
IMR 4166

This fine, extruded propellant is the first in the series of Enduron Technology powders. The main features of the Enduron series are copper fouling eliminator, insensitivity to temperature changes, ideal loading density and being environmentally friendly. IMR 4166 is the perfect burn speed for cartridges like the 308 Win/7.62mm NATO, 22-250 Remington, 257 Roberts and dozens more. Positively, a versatile, match grade propellant.

IMR 4451™
IMR 4451

Another new Enduron extruded powder, IMR 4451, gives top performance in the venerable 30-06, 270 Winchester and 300 Winchester Short Magnum, to name just a few. This propellant is ideally suited for many, many mid-range burn speed cartridges. Simply scroll through the list of cartridges on the Hodgdon Reloading Data Center, and see how many of your favorite cartridges are covered with this fine powder. Once the shooter tries this one in that favorite cartridge, his search is over!

Yep, my bad, 4166. Glad someone finally got it right!

I haven't tried these Enduron powders, but they appear to be IMR's extension into double-based powders. Most traditional IMR powders are single-based.

I doubt the velocity gain will exceed that of Re-17 (also a double-based powder), which I have invested in and used extensively. I don't want to retire Re-17, at least not from what I'm reading and seeing regarding the Enduron group.

Ever seen anyone bring out a new product that didn't claim it to be the best thing since sliced bread???

I'm got plenty of RE powder and loads to go along with it. See no reason to try a new powder based on manufacturer claims.

Nor change to a new powder because it magically controls copper. Never been something that I really worried about.

I haven't seen any RE powders in a coons age in may neck of the woods, but IMR powders are becoming available now. I just picked up 2# of 4451 at my favorite shop an he has an 8# jug also.

I'm down to ~1/2 can of RE17, one can of R#15 and partial cans of the other RE powders and I'm hoarding those until I can get another supply...I'm way too cheep to pay the hazmat charges to UPS unless I can't do it another way.

I also checked the shops 120 miles away...NO POWDER, NO 22LR in ANY of them and hardly any bullets...I was lucky to find a box of Speer 375/235 gr at one shop and a box of Speer 375/270 gr BT's in another.

I'm ready to chamber my 9.5x57 AKA 375/444 AKA 357 JDJ when the reamer gets here tomorrow and I was about to pull bullets from my 375 Ruger and 375 H&H just to get a fully formed case and some velo data...while my bullet order is processing.

4451 Might be a good one for the 9.5x57 and I'll post any data I come up with.

Hey if you run out of the old std then you do what you have to do.

I've narrowed down to just a few powders and was lucky enough to have plenty in reserve before the hording started.

I'm an experimenter so I have to try all the new powders. I remember when there were VERY few powders...4831, 3031, 4895, 4064 etc and when 4350 came out my 25 Neidner turned into a completely new rifle, ballistics wise.

I've found that certain case/cal/bullet weight combos shoot well with several powders but that one or two powders just shine...accuracy/velocity/pressure/density wise.

4451 is a bit too slow for the 375 JDJ/65 cc case, falling between IMR and H4350, but a 375/300 gr bullet with a BC of ~45 at ~2200 fs/3150 ftlbs/~40 kpsi, zero at 175 yds/2350 ftlbs, PB at 205/2250 ftlbs yds and -4" at 300/1900 ftlbs, should make a very nice medium game load...large diameter/heavy bullet at relatively low velos. Definitely gives my 9.2x62 a good run.

4166 would ne a better one of the Enduron powders I think and I will try some of that next time it is available.

Circumstances define what side of the line you end up on...those with and those without components in this case. At one time I thought I had a lifetimes worth of EVRYTHING...SH*T happened, I build too many shooters that used the same powders and SH*T happened again...WHO KNEW??? Hahahahah-ahratz

Luck

I'm waiting to get some 4166 to try in my .308 with 155 grain bullets. 4320 is good but still not quite a replacement for Varget. Hopefully 4166 will step up and it is available.

So here's the question. Are these new powders or just another relabel.

NEW


ALL the Enduron information is available online and in Hodgdon's Basic Reloading manual for those powders and contacting Hodgdon directly will get you the REAL answers.

I think that most of IMR's powder is made in North America while a lot of Hodgdon's powder is imported. To me that means that Hodgdon will remain in short supply while there will be some supply of IMR. I think they're trying to make up for the lack of Hodgdon Extreme powders with the Enduron series.