Home Forums Hunting & Shooting Ask The Gunwriters IMR-4064 really harder on a barrel than AA-2700?

Can someone explain how IMR-4064 is harder on a barrel than AA-2700? I'm looking for a new powder to try in a newly acquired 220 Swift and have run across several threads where folks state IMR-4064 is extremely hard on barrel's. However, I haven't really found a logical explanation as to why, other than it generates more heat than other powders...especially 2700. Can't see where this would be an issue if allowing proper cooling between shots. I've been using IMR-4064 in my other Swift for years and have put appx 800 rounds down the tube(utilizing mostly IMR-4064). It still shoots tiny little groups. With all the talk of being hard on barrels, was thinking about trying a few other powders, most notably AA 2700.

Anyone have real life experience with IMR-4064 prematurely wearing out a barrel vs other powders?

IMR 4064 has a very sharp pressure spike. It has always performed admirably in my 308’s since 1978. I moved on to Varget & subsequently TAC over the last 3 years. I started load development with 4064 in my 300 WSM in 2013. It was quick to reveal just how sharp the pressure spike was with 58 gr’s of powder & 165 gr bullets. Surprised me.

I was warned by my ‘smith that chambered my 22 Creedmoor that it would begin a slow death at 800 rounds. At age 66, it will outlive me. Reckon it depends on how frequent you build a fire in it. I know some bench rest barrels have a life expectancy of about 800. If you were competing with it, I would say find an alternative once your barrel poops out. If you are just hunting, I wouldn’t give it a second thought.

I shot out a used 77v in 220 using 4064 back in the 80's.50 & 52 nosler solid bases. Hot loads ,near max all the time. Shot a few coyotes but mostly used it on pd's 150 to 200 rds on a weekend. Mostly light shooting on the rate of fire ,so the barrel cooled well. At about a total of 3000rds in it I got into a never shot dog town in an hr I fired over 100. Rds from 150 to 400 yds off a Harris by pod laying on a pc of carpet shoot till the better targets disappear then advance thru the town and setup again. By the time I ran out of ammo the throat was alligator skin. But that barrel had alot of rounds thru before that day. I never rebarreled it just traded it off. The gun had a straight 8x leupold on it which I kept for its replacement. 8x isn't quite enough for the range a Swift will give you but you can usually keep a dog in your field of view as he does his rocketman routine. When you get in a situation of multiple unlimited targets at fair range it's damn hard to keep your rate of fire down. That is why a 223 is better suited for dog shooting. I can't tell anyone how many rds using ball powder it would extend your barrel life. I think it's your rate of fire more than anything else, but I can and will tell you h380 drops thru my uniflow measure more consistant than any stick powder, that's a biggie right there . Not to mention more economical brass and powder charges for the 223.mb

The 'experts' have told us for years that double base powders have higher flame temps than single base. Scot Powders based a whole marketing point on that premise. Unless you had two identical rifles, used single base and double base side by side with a borescope...I wouldn't believe a word of it.

"Rocketman Routine". I like that.

I've shoot a lot of 4064 and HAVE shot a lot of it, in a lot of different rifles.

Guess I don't do rapid fire to get the barrel hot enough to brand cattle with it...

I've never had to replace a barrel I've shot a lot of 4064 in....I look down the chamber when the barrels starts throwing shots all over the place.

In my 223s, I shoot a lot of shot gun powder in sage rat loads. Got multiple barrels way on the far side of 30 and 40,000 rounds down the barrels. When I go out and do high volume shooting on the sage rat fields, I normally set up with 3 rifles, and mainly use Blue Dot. I shoot 15 rounds thru one rifle, lean up against the front bumper of my 4 Runner and pick up another one of the other two... shoot 15 rounds and keep rotating them. None ever get hot enough I have to stop shooting them and let them cool. I just do it automatically and I can shoot ALL day rotating 3 rifles, every 15 shots. Don't really need to clean them.. Most I ever shot in a day was like 900 rounds.. so that is 300 rounds in 8 to 10 hours for each.

4064 is used in hunting rifles mainly and range duty/ practice. but I usually keep stock at 24 pounds of it. If I use up one 8 pounder, I go buy another. I do get a lot of trigger time each year. Live 3 miles from my local range.

The early double-based powders were a LOT hotter than single-based powders, but the latest double-based powders aren't much hotter-burning, and the extra nitrogen from their nitroglycerin also tends to strengthen the steel's surface.

Have mentioned this before on the Campfire, but I did an article on the general subject of bore erosion, using a lot of research from various sources, the most interesting a report for the Australian Department of Defence, titled "Understanding and Predicting Gun Barrel Erosion," which can be located by some Googling on the Internet. But it's pretty long, and I condensed the main points in an article on bore erosion in Rifle magazine, which is also Chapter 31 in The Big Book of Gun Gack II.

I had never heard that before reading your post, and it hasn't been my experience.

But might also mention, once again, two things about 2700: First, these days its the same powder as W760 (and the former H414), made in the same plant. They just come in different-labeled bottles.

Also, it's no longer AA 2700, and hasn't been in around 20 years--which was when Ramshot Powders bought Accurate Arms and renamed them simply Accurate.

Thanks John, for the clarification. So is it safe to assume Ramshot didn’t change the formula of the 2700 after they purchased Accurate Arms and renamed them Accurate?

Had wondered about this.

A pard who has since moved on said he used to hear IMR-4064 was hard on throats.

I don't think it was the 4064 as much as it was the scorching hot loads used in the hot 22s and max loads used in the 243 and 6mm with light bullets.