• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

IMR Enduron powders... Who's had good luck with them?

I had really good results with 4451 in 6.5 Creedmoor. It shot bugholes but the velocity node was lower than 4350 in that rifle. I had a node at 2550 with nice low sd. In contrast that rifle likes 4350 in the 2710 range. I still consider it a great powder for 6.5 Creedmoor and use it when I can’t find 4350.
 
I had really good results with 4451 in 6.5 Creedmoor. It shot bugholes but the velocity node was lower than 4350 in that rifle. I had a node at 2550 with nice low sd. In contrast that rifle likes 4350 in the 2710 range. I still consider it a great powder for 6.5 Creedmoor and use it when I can’t find 4350.
I like it in mine too. Running 39.9 and getting 2615speed out of a 25 inch barrel. It’s fun on steel.
 
  • Like
Reactions: MSS
The IMR Enduron powders are double based so they can potentially provide more velocity. They are also advertised as temp stable--though temp stability is affected by a lot of factors.

I picked 4451 over H4350 mainly because I was able to buy 16 lbs of 4451 and Inonly had 12 lbs of H4350. It was bonus that it tuned at 50 fps higher than H4350.

The Enduron powders are easier to find right now and certainly worth trying.
 
I think you all will find the Enduron powders are the exact same stick powders sold by Accurate Arms. Both are Canadian General Dynamics powder.
 
Ok, fair enough. I am still pretty sure it is the same General Dynamics plant that makes both.

Yes, it does. I've wondered about its 'Accurate' lines too. It seems a lot of trouble to be making a third product range, so suspect that the Accurate powders are as per equivalent single-based IMR grades, maybe taken from production lots that are at one end or other of burning rate spreads.

On the wider question, the Sierra VI edition manual that was published last year has a lot of 'Enduron' loads in it. I have noticed a tendency for their maximum loads to be topped out one MV step below Hodgdon 'Extreme' equivalents.

The other 'oddity' is that Hodgdon aside, 4166 gets few or no 223 Rem loads in any source I've looked at. Sierra provides them for 52-55 and 60gn bullets in its 'Bolt Guns' section only out of its many pages of loads. Nothing at all in the 'AR' section. Hodgdon gives data for all bullet weights, but its max charges are around 2gn less than H4895 in the very low levels dictated by pressure-testing in a SAAMI spec 223 Rem short-freebore chamber. That's despite the company's burning rate tables showing it slightly slower burning than IMR-4895, and a few steps slower than H4895 making it look an ideal choice for this cartridge. Is there something about AR port-pressures with this powder? Larger cartridges 308 Win, .30-06 etc - yes, plenty of loads and charges very close to those for H4895, sometimes a tad higher although they only rarely match H4895 velocities in Sierra VI at least.
 
Yes, it does. I've wondered about its 'Accurate' lines too. It seems a lot of trouble to be making a third product range, so suspect that the Accurate powders are as per equivalent single-based IMR grades, maybe taken from production lots that are at one end or other of burning rate spreads.

On the wider question, the Sierra VI edition manual that was published last year has a lot of 'Enduron' loads in it. I have noticed a tendency for their maximum loads to be topped out one MV step below Hodgdon 'Extreme' equivalents.

The other 'oddity' is that Hodgdon aside, 4166 gets few or no 223 Rem loads in any source I've looked at. Sierra provides them for 52-55 and 60gn bullets in its 'Bolt Guns' section only out of its many pages of loads. Nothing at all in the 'AR' section. Hodgdon gives data for all bullet weights, but its max charges are around 2gn less than H4895 in the very low levels dictated by pressure-testing in a SAAMI spec 223 Rem short-freebore chamber. That's despite the company's burning rate tables showing it slightly slower burning than IMR-4895, and a few steps slower than H4895 making it look an ideal choice for this cartridge. Is there something about AR port-pressures with this powder? Larger cartridges 308 Win, .30-06 etc - yes, plenty of loads and charges very close to those for H4895, sometimes a tad higher although they only rarely match H4895 velocities in Sierra VI at least.
I speculated on this last shortage, and the Alliant Powder guy showed up to confirm my speculation for their products. Dunno if it's true for GD, but anyway:

You're a mega defense conglomerate making powder, you're selling all the powder you can make as fast as you can make it. To sell more you need to make capital investments and buy new equipment. Do you buy more of the same ol' equipment from the DuPont days? Hell no, you make investments in the future. New powder making technologies, especially ones that meet new environmental standards (I bet you good money every one of these new powders from various manufacturers meets EU REACH standards), and new customer desires (more temp stable, copper fouling reducing ingredients, etc...).

It may be from the same factory, but it's their offerings for the future. ADI got there first for temp stable stuff, but I've heard (not sure) that their stuff isn't REACH compliant (that's what happens when you move first).
 
IMR 8208 XBR in a long freebore .308 Win shot slightly more accurately than Varget, with a bit more velocity. YMMV. I would not hesitate to use it in competition if the burn rate works for your load.


There are good reports on the web of this powder in .223 Rem, but I don't have personal experience.
 
I've tried IMR4166 and and IMR4451 in several different combinations with 223/308/6.5CM.

I've never found them to produce groups better than one would expect from mid-range factory ammo. They shoot REALLY well at low speeds, but if you run up to typical speeds for the mentioned cartridges, things go to hell in a hand basket quickly.

I ran 4166 in the 6.5 - Berger 140's in a 28inch barrel ~2500FPS and it shot bugholes. Almost any other powder in the same gun could get ~2800+ and have great groups...

Just one mans experience, and I'm curious what luck you've had with the IMR Enduron powders.
For 6.5CM in a 28" barrel I would give IMR4350, 6.5 Staball, H4350, RL15,16, or 17 as well. Other powders if you can find em, VV150, VV160, VVN555 have all given me great and very low SDs. Next buy an EC Tuner brake from erikcortina.com. It allows you to adjust groupings by the tuner reducing harmonics on the barrel and it's build into the brake. Another thing you might want to work on is changing neck tension and seating depth. I have found by extending seating depth you have to of course lower the powder amount. One thing I will warn you about on IMR4350 v H4350. The curves are inverse of each other. As you go up in volume on IMR4350 accuracy goes down and vice versa with H4350. At least that has been my experience on several 6.5CM platforms across different manufacturers and the 6.5 guys ran into the same problem. I've also used Varget and Allegiant 2230 which is good for 223/308 but Ive had some luck in a pinch with it on 6.5. 6.5 CM falls into that area that is right in the middle road of cartridges which has a massive range of possible powders. Case volume has always been better for me out of LP Win and Hornady brass. That isn't to say you'll get the same lifespan out of it, but I find it to be thinner walled than Lapua, Alpha, and Peterson. Ive even necked down 308 with neck turning and found some interesting speed changes for the better, at a lower powder volume, because of course the case holds less powder due to the case wall thickness differences. Hope this helps!
 

That looks like a flyer as a result of something unrelated to your issue. This could be a bad powder drop, even a couple hundreds of a grain can cause this. Could be something that happened when you chamfered/deburred the case mount and got the chamfer too deep. Could be priming seating depth is off 0.002. Could be you're neck sizing a little too deep or not seating the bullet at the correct depth. All of these issues have caused me this exact problem. Without having all the data for this outing (speed, ES, SD, etc) hard to say what couldve caused it. Although, a pull low right on a right handed shooter could very be trigger control or even wrist control. I've done this so many times and its so frustrating to have this happen. When it does I try to find the EXACT same sight picture and repeat the trigger pull/wrist dynamics as well just to see if I can recreate it and therefore figure out if it's something with my reloading process or myself the shooter. You're not alone, I can promise you that.
 
Let’s not forget 8208. It works well in 223, I’ve not tried it in anything else yet.
8208 is great! But unlike the other Enduron powders, it's made in Australia. Anecdotally, it's quick Varget developed for the Aussie military 223. Superb in the Grendel with 123's. Haven't tried it in 223 or 6br yet.
 
Yes, it does. I've wondered about its 'Accurate' lines too. It seems a lot of trouble to be making a third product range, so suspect that the Accurate powders are as per equivalent single-based IMR grades, maybe taken from production lots that are at one end or other of burning rate spreads.

On the wider question, the Sierra VI edition manual that was published last year has a lot of 'Enduron' loads in it. I have noticed a tendency for their maximum loads to be topped out one MV step below Hodgdon 'Extreme' equivalents.

The other 'oddity' is that Hodgdon aside, 4166 gets few or no 223 Rem loads in any source I've looked at. Sierra provides them for 52-55 and 60gn bullets in its 'Bolt Guns' section only out of its many pages of loads. Nothing at all in the 'AR' section. Hodgdon gives data for all bullet weights, but its max charges are around 2gn less than H4895 in the very low levels dictated by pressure-testing in a SAAMI spec 223 Rem short-freebore chamber. That's despite the company's burning rate tables showing it slightly slower burning than IMR-4895, and a few steps slower than H4895 making it look an ideal choice for this cartridge. Is there something about AR port-pressures with this powder? Larger cartridges 308 Win, .30-06 etc - yes, plenty of loads and charges very close to those for H4895, sometimes a tad higher although they only rarely match H4895 velocities in Sierra VI at least.
Laurie - despite other posts - I was disappointed with the first trials of 4166 in 223. However I qualify this by stating that the brass was ADI, which has a lower (5.56 like) capacity. The load was 24.5g with a 69g Nosler Competition, somewhat compressed, and it was shooting at the bottom of the 600yd F-class target. I haven't tried it again - yet! Primer was Federal Gold. My usual load is 25.4 Varget with 69's/24.4 with 75's. I will try it again. maybe with a bit more neck tension - maybe a different primer?
But looking at the data - it certainly jumps up in pressure quickly at higher loads - and this may cause issues with self loaders - Im not saying that a good load cannot be made - but is Hogdgon being a bit careful - by not recommending it's use in 223?
 
IMR8208 works excellent in my 6.5TCU with 130gn projectiles BUT IMR7977 and 140's pattern like a shotgun in my 6.5SAUM which is a pity as its easy to get here currently unlike almost every other powder and 6.5 Projectiles sadly
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,851
Messages
2,204,884
Members
79,174
Latest member
kit10n
Back
Top