H335 and temperature changes - - More Questions

Hidalgo

Hidalgo

Well-known member
Has anyone ever actually experienced any pressure/velocity/POI variations with H335 due to temperature changes?

I'm going to SD in 3 weeks and have some AR loads that I might be concerned about if the temps actually have a big effect on this powder.

Anyone ever see this first-hand?
 
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Many powders and expecially Ball types will have higher pressures when heated. If these rounds are on the ragged edge, keep them in the shade. You will know as the day progresses how they are doing. This is not just going to make an OK load destroy your gun on the first round. You will start to see pressure signs as the temps rise.

One word of caution, if your barrel and chamber is heated up, keep the bolt open till you acquire the target, close the bolt and take the shot. My nephew ruptured a 17 rem case a few years back with a peak load and froze the case in the bolt face. He had shot too long in high heat of north Texas. Loaded a round and began to look for another shot. Five minutes later he took a shot and ended that rifle for the day. The rifle was not damaged other than the ejector quit working till I took it out and replaced the pin and spring.
 
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One word of caution, if your barrel and chamber is heated up, keep the bolt open till you acquire the target, close the bolt and take the shot.



Good advice Randy. But that ain't gonna work with an AR. Which gives me even FURTHER concern, because of rounds are going to be sitting "cooking" in the chamber between shots.

Am I dreaming?......or did I actually read somewhere about a fellow who kept his ammo in an ice chest along with one of thise frozen gel packs? /ubbthreads/images/graemlins/confused1.gif
 
Yes many people will keep them in an ice chest. I used those little soft sided picnic coolers with no ice. Just wanted them to stabilize
 
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One word of caution, if your barrel and chamber is heated up, keep the bolt open till you acquire the target, close the bolt and take the shot.



Good advice Randy. But that ain't gonna work with an AR. Which gives me even FURTHER concern, because of rounds are going to be sitting "cooking" in the chamber between shots.

Am I dreaming?......or did I actually read somewhere about a fellow who kept his ammo in an ice chest along with one of those frozen gel packs? /ubbthreads/images/graemlins/confused1.gif



You're not dreaming. I had problems with H-335 in SoDak in a .222 Mag.

The second day (and for the rest of the trip), I put the ammo in the cooler on the sandwich tray (above the ice).
I don't shoot it any more.

Keep it in zip lock bags so it stays dry. Don't let the barrel get that hot.

And I'm not the only guy that has done this.

If it's not too late, I would load with BenchMark.

.
 
I stopped using H335 years ago because of the instability problem. There are so many other great powders for 223, W748 being abut the best there is for that caliber, there is no need to even have H335 in the cabinet any more.
 
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One word of caution, if your barrel and chamber is heated up, keep the bolt open till you acquire the target, close the bolt and take the shot.



Good advice Randy. But that ain't gonna work with an AR. Which gives me even FURTHER concern, because of rounds are going to be sitting "cooking" in the chamber between shots.

Am I dreaming?......or did I actually read somewhere about a fellow who kept his ammo in an ice chest along with one of thise frozen gel packs? /ubbthreads/images/graemlins/confused1.gif



You can try to push the bottom of the bolt catch while firing and get the bolt to stay open. When your ready to shot hit the release.
 
Hidalgo, 600 yard Highpower Shooters single feed every weekend. The Mag will keep the bolt open. lay a round in the gate and when you acquire the next shot, hit the release button and you are ready to go. You will be impressed with how fast this can work with a little practice
 
In my .223 I notice about 130 fps increase from 40* to 70*. I don't feel comfortable shooting it above 70*, but I just hunt coyotes in the winter with it.
 
My '335 loads run on the edge at 75* I have tried them at 95* and they were way too HOT!!!...my 50Vmax load in my 223AI is running 3750 at 75*, and 3600 at 30*. Definately not a load I would shoot PD's with.
 
I shoot 335 in 3, .223's and have shot in 110 deg. heat with no probs. but I try to keep them in the shade and in a cooler without ice.
 
Hidalgo, there is a guy in Phoenix (works part time at Randalls Firearms, HIS name is Jan)that tested some powders (mostly Hodgdon Extreme like H4350). He is very meticulous. He did say the ice chest ammo and the open air ammo shot very similar velocities. I did not ask him if he also tested some of the Ball powders mentioned.
 
I've shot hundreds of pounds of H335 and T2208 ball powder in AR 15 and M 16's. If you load to a maximum charge in the winter it will blow the primer out of the case in the heat of the summer, In Arizona. It might be different in Alaska. I've had good luck with accuracy using 335, but at this point there are a lot of better powders available. I only use it in my 223AI currently, and that will change when the last keg is gone. I really like Hodgdon Benchmark right now.
 
Dan, are you finding the Benchmark giving you the same velocities as will the '335? I don't even know how many pounds of '335 I have fired, but will try something new if it's better.
 
I'm getting similar velocity with Benchmark and better accuracy. It's a very small grain powder, kind of like Varget, measures well. You can check Hodgdon's site for some velocity figures.
 
There was some testing done for an article in "The Varmint Hunter Magazine." He shot rounds with the powder at different temperatures and there was almost no difference in pressure or velocity with different temperatures. However, the temperature of the chamber and barrel made a big difference in pressure and velocity.

Jack
 
The loads in question are 26.0gr of H335 under a 50gr Blitzking.

According to Sierra's data in their manual, this is a MAX load for an AR.

BUT...it is 2.0gr UNDER max for their bolt data.

How would you guys feel about shooting these in a bolt gun in 90 degree weather? I just got a new .223, and it would sure be nice to use these 400 rounds instead of having to load more. (that is, if the rifle likes the load).

These loads have shown very little pressure signs so far in the AR. The primers are showing a very small amount of flattening, but it is very little.
 
I've been using H335 with the 40 grain V-Max out of my CZ in .223. Loads I worked up in the early spring here in western Washington were way to hot when I shot them later in Idaho. Tempature difference of about 30 degrees. (50's verses 80's) After about 5 or 6 rounds I put it away! I ended up pulling all the bullets and reducing the loads. A royal pain in the arss when you have 300 of 'em!!
 
As of last Friday I can tell you 26.5 under a 55 FMJ is way too much. I used these loads early in the spring approx 40 deg not a problem. Shot them last Friday at 78 deg and blew a primer on the third shot. I was shooting an AR-15 and the primer got stuck between the upper receiver and the bolt carrier, the only way I could get it apart was a hammer and a brass punch. Needless to say my upper receiver has a nice drag mark all the way down it where the primer was gouging into the upper while I was pounding the bolt out. My suggestion would be to use another powder for sure. I just started using 335 last spring and have stopped as of last Friday.
 
Stevo,
Hey I have never noticed any pressure signs in all the rounds I have loaded for the Stevens .223 even in the heat. But what I can tell you is that I have used the same load for several years for yotes in the winter and rockchucks in the summer and accuracy has been top notch at both times of the year with H335. I wouldn't worry about it at all. Most of the 900+ rounds of that load down the tube were in the summer months of 75-100 degrees outside. And during all the summer months it preformed the same deadly accurate with NO complications. I use 25.5 grains H335 and 55 Grain Vmaxes with CCI 450 Mag primers. Good luck
 


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