44 Mag - H110 Velocity Drop

[MOP.GBB]

I know H110 is temp sensitive … or at least that seems to be the consensus, but this seems a bit much for a 23 degree drop in temp … from 72 to 55 degrees. These are 5 round groups with .5 grains of H110 increase between each group. Started at 18.0 and ended at 20.5

Using 300 grain, gas checked, pan lubed cast bullets out of a Lee C430-310-RF Mold. WLP primers, H110.

Velocity difference between Day 1 at 72 degrees and Day 2 at 55 degrees:

Group 1 (18.0 gr): -78.3
Group 2 (18.5 gr): -93.5
Group 3 (19.0 gr): -136.6
Group 4 (19.5 gr): -156.7
Group 5 (20.0 gr): -146.8
Group 6 (20.5 gr): -149.8

This wouldn't be caused by a 23 degree temp drop would it?

It's possible my scale wasn't calibrated correctly, but for that to be the culprit, I would think the velocity drop would be uniform across all groups. The groups seem to progressively worsen, the stabilize.

Would love to hear your thoughts!

 

[murf]

try cci 350 primers when you get a chance. h110 powder can do strange things, but when everything is right there is none better for what you are doing.

luck,

murf

 

[mcb]

I have seen similar changes in my 450 Bushmaster loads using H110. I lost nearly ~80fps fps going from 85 deg degrees to 50 deg.

Assuming you are shooting it in a revolver, I think your effects are this large due to the short barrel. H110 is already on the slow side for short barrels and thus a reduction in burn rate due to temp is going to have a bigger effect in shorter barrels.

I have quit using H110 in 44 Mag for this reason along with the excessive muzzle blast/flash. I use 800X in 44 Mag and save the H110 for the 450 Bushmaster and 410 shotgun.

 

[MOP.GBB]

I have seen similar changes in my 450 Bushmaster loads using H110. I lost nearly ~80fps fps going from 85 deg degrees to 50 deg.

Assuming you are shooting it in a revolver, I think your effects are this large due to the short barrel. H110 is already on the slow side for short barrels and thus a reduction in burn rate due to temp is going to have a bigger effect in shorter barrels.

I have quit using H110 in 44 Mag for this reason along with the excessive muzzle blast/flash. I use 800X in 44 Mag and save the H110 for the 450 Bushmaster and 410 shotgun.

Ok, that makes sense. Yea, this data is coming out of a Ruger Red Hawk 7.5 in barrel.

 

[Charlie98]

WLP primers, H110.

Like Murf suggests, try a true Magnum primer. I know the WLP's are supposed to be either or, but I've found in testing velocity variations with WLPs vs CCI 350's. They work great with heavy charges of other powders... like IMR4227 or 2400, but I only use 350's with H110/W296.

 

[WrongHanded]

If you're interested in trying a different powder, 300-MP works well with 300gr bullets in .44 mag. And out of a 7.5" barrel, it's likely to give you some impressive results. I don't know if it is less temperature sensitive than H110, but it might be worth some experimentation.

 

[sisyphus]

I read this and then thought to change what powder I was going to buy for 41/44 and landed on Lil Gun. Then I read stuff about Lil Gun burning hot and potentially damaging barrels faster. Then I thought H110 is generally on the fast side, a drop in the cold is still going to make it an above average or at least average choice. After all that I think I'm still getting H110 for my revolvers.

 

[mcb]

I read this and then thought to change what powder I was going to buy for 41/44 and landed on Lil Gun. Then I read stuff about Lil Gun burning hot and potentially damaging barrels faster. Then I thought H110 is generally on the fast side, a drop in the cold is still going to make it an above average or at least average choice. After all that I think I'm still getting H110 for my revolvers.

I think you have that backwards H110 is a very slow burning pistol powder, its even relatively slow as far as shotgun powders go. H110/W296 is some of the slowest powders recommended for a 300 gr bullet in 44 Mag. The only thing Hodgdon lists that is technically slower is IMR 4227 and its sits right next to H110/W296 on most burn rate charts. This is the reason you get such huge fireballs and so much muzzle blast from H110 in 440 Mag revolvers. You are burning 10-15% of the powder out in front of the muzzle in many cases.

 

[sisyphus]

I meant that muzzle velocities were on the faster side with H110, at least on the guides I have.

 

[Mr. Zorg]

My Speer Reloading Manuals, and their online data, always recommends a magnum primer with H110 & W296 (same stuff different label), and of course it's not just any magnum primer but a CCI 350 specifically used to develop the load dta with that powder.

I wouldn't classify a 7.5" barrel as "short" for a revolver. My Astra 44 Magnum with 2 and 3/8 inch barrel, yep that's short. But my Llama Super Comanche revolvers with 6" barrel on one and 8 and 3/8" barrel on the other - not short in my book.

 

[Charlie98]

I meant that muzzle velocities were on the faster side with H110, at least on the guides I have.

I've found, generically speaking, H110/W296 to produce the highest velocities of most common Magnum-type powders, followed by 2400, and then IMR4227... this in both pistols and rifles. There are other powders, of course, AA#9, and 300MP (as WrongHanded mentioned...) but I'm not familiar with them.

 

[mcb]

I meant that muzzle velocities were on the faster side with H110, at least on the guides I have.

Sorry, I misinterpreted you. You are correct, despite the inefficiency of H110 there are few powders that result in more velocity, especially with the heavy for caliber bullets in 44 Mag.

 

[buck460XVR]

I have found H110/W296 to be very temperature sensitive, especially in larger cases like .44 mag and .460. One reason I have gone to IMR4227 in both for hunting type loads that will be used in temps from 80 degrees to -10 or more below. Not so much in smaller cases like .357. In large cases like .44 and above with a max or close to max charge, what type of magnum primer is going to make no difference in temperature sensitivity. The temperature sensitivity was made apparent to me when I looked at primers from the same batch of 240 gr JSPs over 24.3 gr of H110 shot from the same gun. 6 shot at the range in 70 degree weather to make sure how they shot, the primers were flat. Two months later while deer hunting, I shot two at a buck and when I put the empties back in the box along side the others, the rounded shoulders of the primers were readily apparent next to the flattened ones. Never measured the velocity difference, but the difference in pressure was readily seen. Similar scenario with IMR4227 and there was no difference in primers. For the most part, the difference of 150-160 fps would not be a factor. But when hunting deer out to 100 yards or so, it (+3")could be the difference between a boiler room shot and just a leg/brisket wound.

 

[Mr. Zorg]

Thanks for the personal insight on the temperature sensitivity of H110 / W296 being more evident in .44 and larger bore cartridges. I hadn't seen anything published on that.

Speer also advises magnum primers in cartridges planned to be fired in ambient temperatures of 20°F or lower for better odds of consistent ignition in those temperatures. M. L. McPherson has similar advice and expounds somewhat on theory regarding reduced plasticity of smokeless powder kernels in such temperatures having effects but I don't believe that angle has really been fully tested by anyone.

 

[derek45]

a magnum primer and good FIRM roll crimp helps with h110/win296

 

[murf]

i forgot about the roll crimp. i would go further than @derek45 and say heavy roll crimp.

murf

 

[Charlie98]

and say heavy roll crimp.

That's where the Patented Charlie98 Death Grip Crimp comes in!