H380 problems

[Brownie36]

I loaded 500 rounds of H380 for my 22 250 ar 10 this winter and it was perfect. I went to Texas this past weekend prarie dog hunting in 95 degree weather and was blowing out the primers!! I know it’s the temp change . My question is if I have my 62 grain bullets close to the lands can I seat the bullet deeper to reduce pressure enough to use them in hot weather or just keep them cool while I shoot them?

 

[Toddmack]

Actually that should INCREASE pressure. I'm not a Road's (joke) Scholar and if I'm wrong someone that actually knows something will chime in here to correct me. In my limited experience, when limited by mag length loading longer seemed to drop pressure.

Yes, H-380 is pretty temp sensitive. I loaded some very hot .243 rounds with 380 and 58 Vmax's shot through a Savage 99C. Lots of ejection problems and I almost had to gain weight to resize the brass(I'm 225).

Shot in July.

 

[Straightshooter1]

I loaded 500 rounds of H380 for my 22 250 ar 10 this winter and it was perfect. I went to Texas this past weekend prarie dog hunting in 95 degree weather and was blowing out the primers!! I know it’s the temp change . My question is if I have my 62 grain bullets close to the lands can I seat the bullet deeper to reduce pressure enough to use them in hot weather or just keep them cool while I shoot them?

If you seat your bullets "deeper" (assuming you mean deeper toward the lands), pressure will be reduced . . . at least until you're on the lands. Whether or not you can offset the effects of the increased heat depends. It's possible depending on just how much more "deeper" you can really go. And in trying to do so, I would expect that to kinda mess up your accuracy. You'd have to do some experimenting to really find out how any of that might work. H380 is pretty temperature sensitive . . . see pic below as to how it compares to some other powders:

 

[JSH]

I just ran some through my 22-250 last week. 38.0-H380 , 50 and 55 grain bullets. It shoots exceptionally well, I had zero problems. I did keep an eye on how hot the rig was and kept a towel over the top of the ammo.
If I shot a fairly long string, then chambered a round and it was in the chamber for a few minutes with no where to go, I replaced it with another. I think maybe letting a round “cook” in the chamber me be an issue for some?

I didn’t chrono these and it came back and bit me. I went for pure accuracy and didn’t chase another node.
Some factory Nosler 40 grain in 223, advertised speed of 2700, had less drift in the 30mph we were dealing with. Makes me want to review the thoughts of speed vs heavy bullet weight.

The 40 was driving drifting say 4-6”, where the 50 and 55’s were close to 12”.

 

[Brownie36]

I just ran some through my 22-250 last week. 38.0-H380 , 50 and 55 grain bullets. It shoots exceptionally well, I had zero problems. I did keep an eye on how hot the rig was and kept a towel over the top of the ammo.
If I shot a fairly long string, then chambered a round and it was in the chamber for a few minutes with no where to go, I replaced it with another. I think maybe letting a round “cook” in the chamber me be an issue for some?

I didn’t chrono these and it came back and bit me. I went for pure accuracy and didn’t chase another node.
Some factory Nosler 40 grain in 223, advertised speed of 2700, had less drift in the 30mph we were dealing with. Makes me want to review the thoughts of speed vs heavy bullet weight.

The 40 was driving drifting say 4-6”, where the 50 and 55’s were close to 12”.

I’m seeing the same thing in 30 mph winds. My bolt gun 22 250 with 55 gr had less drift than my ar 10 22 250 with 62 gr. I’m thinking speed in these conditions is more effective.

 

[Brownie36]

Actually that should INCREASE pressure. I'm not a Road's (joke) Scholar and if I'm wrong someone that actually knows something will chime in here to correct me. In my limited experience, when limited by mag length loading longer seemed to drop pressure.

Yes, H-380 is pretty temp sensitive. I loaded some very hot .243 rounds with 380 and 58 Vmax's shot through a Savage 99C. Lots of ejection problems and I almost had to gain weight to resize the brass(I'm 225).

Shot in July.

I’m not an expert either. That’s why I’m asking but I was thinking about seating more into the case to get some blow by before the bullet seals the gas when it gets into the lands. I have the bullets loaded longer than col from the manual. I had plenty of magazine room so I seated them close to the lands with extreme accuracy.

 

[Outrider27]

If you seat the bullets deeper into the case, the pressure will increase. Until you develop a hot weather load, I would suggest storing them in a small cooler, along with one of those re-freezable ice packs. I have a soft side insulated cooler for one 6 pack of soda that works perfectly for this. Just a thought.

 

[thatguyshm]

I think you are trying to get the Weatherby effect with a large jump decreasing pressure , but without increasing actual freebore, I'm not sure if it will work. May be a buffer change could do something, but I doubt it. You probably have a winter only load made up now. We've all been there .

 

[Bill K]

No, seating deeper will most likely raise pressure and make it worse.
Your loads are just not suited for the temp you are shooting them at, there .

 

[K22]

I also encountered problems with H380 in the 22 250 while hunting ground hogs in 90 degree+ weather. Although H380 was one of the most accurate powders I ever used in the 22 250, I switched to IMR 4064 and the problems disappeared. I've also used Varget, H 4895 with success and no pressure surges in hot weather.

Surprisingly, the tightest groups I ever shot with the 22 250 (14" twist) was with IMR 4350, 50 grain Nosler BT's, and Federal match primers but at the cost of lower velocity in the 3,500 f/s range.

 

[drover]

Keep your ammo loaded with H380 in a small icechest with a re-freezeable ice pack and it should be fine. Just don't let it set in a hot chamber for an extended period before shooting it, lay it on the load ramp and when you are ready to shoot close the bolt and chamber it just prior to firing, if you don't shoot right away then extract it from the chamber so it doesn't absorb the heat from the chamber.

I have done this with H335 which is temperature sensitive and it worked out well.

drover

 

[Brownie36]

I think you are trying to get the Weatherby effect with a large jump decreasing pressure , but without increasing actual freebore, I'm not sure if it will work. May be a buffer change could do something, but I doubt it. You probably have a winter only load made up now. We've all been there .

I’m going to try the weatherby effect this weekend. I’ll let you know what happens.

 

[sundance]

You now have a morning rifle. I did that once with about 400-500 rounds .Shot great at 65 degrees and at 95 degrees every bolt lift was affected. That became my early morning rifle for a few trips until that ammo was used up. Eastern Colorado can easily hit 100+ degrees in the summer -no place for hot loads with your face next to the bolt.

 

[Rust]

Weatherbys run a long throat, that's how they get the so called "Weatherby Effect". Seating bullets deeper with a charge you already know is too hot in hot weather is just a plain bad idea.

But let us know how that works out for you if you decide to go ahead and do it. Could make for an interesting cautionary tale on what not to do.

 

[3Sigma]

How hot are the loads?

I found the same problem with 4064 when running close to max pressure (~3800 fps 55gr Sierra GameKing). Great velocity and grouping at ~40°F, hard bolt lift and flattened primers at 85°F. Still shoots great, just too hot of a load for my taste. I may use it for deer hunting if I want to try a .22 caliber.

I wanted a better throwing powder for varmints, so I switched to H380 running 38gr with the 53gr Vmax at ~3630fps at 30°F. It shot so good during seating depth testing that I just kept it (< .25" groups on a Savage 12FV!) I only experienced ~15 fps increase when shooting at 80°F last weekend, still grouping under 1/2" at 100 yds.

I decided that chasing velocity is not good with these powders unless you are loading at the range. If I were you I'd put those loads away and shoot them in the cold. Or pull the bullets and reduce the load to a lower node.

As always, YMMV.

 

[Brownie36]

Weatherbys run a long throat, that's how they get the so called "Weatherby Effect". Seating bullets deeper with a charge you already know is too hot in hot weather is just a plain bad idea.

But let us know how that works out for you if you decide to go ahead and do it. Could make for an interesting cautionary tale on what not to do.

Did you read all of what I said or just get in rush to belittle me?