Sierra 300gr .44s

[no.5enfield]

I've got a number of these JSPs that I'd like to load. The powder on hand is H110. Hogdon's site and my manual have data for 300gr XTPs, but not these Sierras. My concern is that the Sierras are spec'd to 1.73 oal, vs 1.6 for XTPs. How does this affect my load data of 18-19 grains of H110?
I loaded one with 18 grains and test fired without issues, but I want to make sure I'm not playing with fire.

 

[Ru4real]

How did the case look? Sooty? Primer still have round corners, or did it flatten some? Did you find any powder granules in the spent case or in your barrel?

H110 is pretty forgiving, I’ve found. When pressure is way low, you can get clumps of unburnt 110 left in the case. When pressure is a little low, you will find grains of 110 in the bore and in the case and sooty cases.

The best indicator I’ve found for good pressure is a combination of spent case observations, spent primer appearance, low velocity spreads and deviations for 10 shot strings, and most importantly good groups.

If your revolver allows, one option is to load the JSP round 0.125” longer to account for the longer bullet.

 

[Barbaroja]

Prehaps measure the length of the bullet that would be inside the case and compare the two. that would give you some idea of it will be creating more or less pressure inside the case and you can decide for yourself.

Id guess the difference would be negligible, and you would be able to start at the listed starting charge for the other 300gn bullet.

 

[Tempus Tom]

Prehaps measure the length of the bullet that would be inside the case and compare the two. that would give you some idea of it will be creating more or less pressure inside the case and you can decide for yourself.

Id guess the difference would be negligible, and you would be able to start at the listed starting charge for the other 300gn bullet.

This is what I did.

While I don't have the exact data in front of me, I believe I used 19 grains of IMR 4227 and they shot well from my S&W revolver.

However, I remember reading something about the 300 grain bullet from Sierra and they recommended it only being used in revolvers due to feeding issues in lever guns (from the long OAL). But if they feed in your gun, then I wouldn't worry about it.

 

[no.5enfield]

Thanks for the tips. I'll check the brass out again when I get home and see what the primer looked like.

 

[sparkyv]

If it were me, 18.0gr is just fine, if on the low side of the charge range. I'd be incrementally/safely be loading those babies upto a couple of grains more to see what my revolver likes.

 

[BBarn]

The 18-19gr charge of H110 should be safe behind the Sierra 300gr. bullet seated to the longer OAL. I believe the Sierra data starts at about 18.5gr. of H110 using that bullet.

 

[no.5enfield]

Thanks, I meant to call Sierra this week, but was really busy at work every time it crossed my mind.

 

[GarrettJ]

My Sierra 5th Ed. manual shows 18.6 to 21.8 gr. H110 with their 300 gr. JSP, loaded to 1.735". That's in the handgun section.

Interestingly, the rifle section of the book lists 16.9 to 20.0 gr. at the same OAL.

If you want another point of reference, Lyman 50th also lists the 300 gr. Sierra. They give a range of 19.6 to 20.5 gr. H110 with a 300 gr. Sierra JSP, loaded to 1.720" in both the Pistol and Single-Shot sections. They don't list a 300 gr. bullet in the Rifle section of the book.

 

[no.5enfield]

Thanks, those first loads you mentioned have a much larger min-max range than I'm used to seeing for H110.

 

[GarrettJ]

Thanks, those first loads you mentioned have a much larger min-max range than I'm used to seeing for H110.

Yeah - I had the same thought. Enough so that I pulled my Sierra 4th Ed. (1995) out from the back of the bookshelf to check. It listed the sam range.