H110 load data for 357 Magnum

[Reaper_6A]

I have been reloading for a few years now and am pretty proficient at 9mm, .40 cal, 45 ACP, and 223 Rem. However the 357 Magnum is a completely different beast. I have an M&P R8 and am using 158gn Hornady XTP bullets, Starline Brass, CCI Magnum Primers (550), and Hornady H110. I have a medium to hard crimp and feel I am close to achieving optimal performance. If someone could review my data below and tell me what they think I would appreciate it.

The top data is from Magtech 158gn SJSP ammo, bottom is from my reloads.

Magtech 158gn
8 shot avg - 1065 FPS (box claims 1200 from 6in barrel)

Reloads 158gn XTP
8 shot avg - 1043 FPS (Hodgon claims 1418 from 10in barrel)

COAL 1.278 - 1.282
OAL 1.578 - 1.581
Powder 16gn H110
Primer CCI Magnum
Average bullet weight 158.4gn

String 1
964.4
1066
1040
1016
1104
1005
1053
1096

High 1104
Low 964.4
ES 139.6
AV 1043
SD 47.08

Any Advice from someone experienced with reloading using H110 would be appreciated.

 

[Bruce51]

Hodgdon H110

Welcome to the forum.

What you will find is that different guns will give different results as far as velocity.

The data provided by the companies is only a guideline. Different guns, bullets and primer combinations will yield different results.

That being said I find your results to be pretty much within the normal range for H110.

I have two .357 magnums with four inch barrels.

With 16 grains of H110 and a 158 JSP bullet one will yield approximately 1040 fps.

The other gun with the same load combo averages 1165 fps.

Two guns both Smith & Wessons both four inch barrels one over a 100 fps faster than the other.

Sixteen grains is as low as I will go with H110. This is due to trying to duplicate Remington 158 JSP velocity in a 1894 Marlin.

While I found that 17 grains was needed to duplicate the Remington load 16 grains was only 100 fps slower and showed less signs of pressure.

H110 is a very flashy powder especially in a revolver. Yet it works well and is easy to work with in a powder measure.

If you have more questions there is plenty of help available here.

BLM

I should have mentioned that loading density is very important with H110.

Reviewing my data shows that 16 grains produces velocities which are very close.

Example 1167/1165/1173 fps for a 158 JHP

 

[Rule3]

Bruce covered it well above.

Main thing is you are at the start load and H110 works best at or near the max load. You want to be more at 16 grains.

You will not get the velocity they claim out of your gun (I have the same gun)

How are you weighing/dropping your powder?

From what you posted there is nothing "wrong" that I can see. You want a very firm crimp on the cannelure (crimp line) of the bullet

If you have 2400 powder try that and no Mag primer needed. Much more user friendly.

 

[andyo5]

When I used H110 with 158g bullets, I used 14.5g and got around 1000FPS. But the accuracy was really good. I am considering using it again with a higher powder charge. I have tried 11g of Blue Dot, and accuracy was outstanding but velocity was very dependent on ambient temperature and that scared me. I also have used 14.2 to 14.5g of 2400 with good accuracy results, but not as good as H110. Velocity was in the 1200 to 1300 range.

 

[ArchAngelCD]

Hodgdon does not recommend you download H110 more than 3% from the Max. Hodgdon lists the Max as 16.7gr H110 under a 158gr jacketed bullet. I can not figure out why they tell us not to download more than 3% yet their min/max is the usual 10% reduction for H110/W296...

When loading a 158gr JHP or JSP bullet my usual charge is 16.4gr W296 with a CCI550 primer.

 

[scooter123]

If you look at the Lyman 49th you'll find their Starting Load for 357 Magnum with H-110 and a 158 grain Hornady JHP is 16.3 grains and the Maximum charge is 17.0 grains. Since the pressure listed for this data is in CUP it's pretty safe to assume that it is somewhat dated data but it's also an indication that you can step up your charge level.

BTW, I've loaded using Lyman's starting loads for H-110 in 357
Magnum and saw no signs at all of excessive pressure. About the only potential issue was the incredible amount of muzzle flash and blast with the 125 grain XTP I was loading with. Caused me to conclude that H-110 is just too slow for a lighter bullet.

Your lack of velocity production and the high degree of variance in the produced velocities lead me to believe that you aren't getting the pressure into a good working range for your powder. I would recommend that you try increasing your charge amount and do more testing. I'll also recommend that if at any point you start to have cases sticking in the cylinder to back away from that charge level by at least 1/2 grain. Because sticky extraction is a pretty reliable indicator that pressures are getting too high.

 

[MichiganScott]

I load 16.3gr of WW-296 behind 158gr bullets. I started using that charge when Winchester first offered 296 to the public and listed a max charge of 16.5 grains, which I found caused sticky extraction. The last time I chrono'd that load, it barely made 1100fps. I suspect the OP's chrono data is correct and he could easily up the charge.

 

[Rule3]

Hodgdon does not recommend you download H110 more than 3% from the Max. Hodgdon lists the Max as 16.7gr H110 under a 158gr jacketed bullet. I can not figure out why they tell us not to download more than 3% yet their min/max is the usual 10% reduction for H110/W296...

When loading a 158gr JHP or JSP bullet my usual charge is 16.4gr W296 with a CCI550 primer.

I have been questioning that for years

Look in the Hornady manual. Same thing. Way over a 3% reduction. There is a post here long ago with Skip were we argued over this. He claimed it was the way it was written meaning the 3% only applied with UN tested loads. I do not read the warning that way myself. To much semantics involved.

 

[Bruce51]

data

I found the OP's chronograph data interesting as it verifies at 15 grains H110

is not at an optimum loading density.

Has anyone ever tried a 180 grain bullet with H110?

I think that bullet would work well in the Marlin with the microgroove barrel.

Some day I need to give it a test run.

BLM

 

[Rule3]

I just want to clarify or disclaimer for the OP

I do not recommend loading max loads especially for folks that may be new to reloading.

H110/Win 296 is just one of those powders that does better at the higher end of the charge data. It is a very slow powder and fills the case up a lot so it's pretty hard to blow up a case or gun with it. Just make sure you don't compress it and stay below the absolute max and you will be fine to shoot another day.

What is so weird is that Hornady tested the 158 gr XTP with H110 and their range is 12.7 up to 15.6 grains!
(Colt Python 8" barrel)

Hodgdon (with the same bullet) shows 15.0 to 16.7 grains!

10" test barrel

 

[Reaper_6A]

Using the advice provided by you fine gentlemen I will try some more this weekend loaded at 16gn and 16.2gn with a slightly firmer grip and see what I can get out of them.

 

[A.O.]

Ahh, good read here. I just acquired my first 357 mag/38 and have lots of H-110 on hand. Just bought 200 158gr XTP's and 250 plated 158gr hollow points to play/experiment with. Gives me a good frame of reference to start with.

 

[Rule3]

Remember H110 requires a Magnum primer.

 

[A.O.]

Remember H110 requires a Magnum primer.

Well in a 357 mag anyway..

 

[ArchAngelCD]

I found the OP's chronograph data interesting as it verifies at 15 grains H110

is not at an optimum loading density.

Has anyone ever tried a 180 grain bullet with H110?

I think that bullet would work well in the Marlin with the microgroove barrel.

Some day I need to give it a test run.

BLM

Yes, I did some 180gr loads with W296/H110 and a CCI550 primer.
With W296 and a 180gr Hornady XTP bullet from a 4" barrel the AV was 1056 fps and from a Marlin 1894C the AV was 1495 fps.

With a 180gr Cast Performance WFNGC bullet loading H110 from a Marlin 1894C the AV was 1547 fps.

 

[Bruce51]

Thanks Arch! I see that Sierra makes a 180 grain bullet as well.

Did you find the 180 grain bullets to give good accuracy?

I stopped testing in my Marlin when I found the 160 grain Speer half jacket gave me the best groups. Try to find that bullet now.

I have always wanted to do a retest with a 180 grain as Microgroove barrels seem to prefer long bullets.

BLM

 

[ArchAngelCD]

Thanks Arch! I see that Sierra makes a 180 grain bullet as well.

Did you find the 180 grain bullets to give good accuracy?

I stopped testing in my Marlin when I found the 160 grain Speer half jacket gave me the best groups. Try to find that bullet now.

I have always wanted to do a retest with a 180 grain as Microgroove barrels seem to prefer long bullets.

BLM

The 180gr bullets were just as accurate as any others. I did however find the 170gr Sierra JHC bullets to be the most accurate in my handgun and levergun. Those and the Sierra 150gr JHC bullets are my favorites in the .357 Magnum.

The numbers from 170gr Sierra JHC bullets in my levergun.
17.0gr Lil'Gun - CCI-550 primer - AV=1793 fps (that's amazing velocity!)
15.5gr H110 - CCI-550 primer - AV=1699 fps

The numbers from 150gr Sierra JHC bullets in my levergun.
15.5gr 2400 - Win WSP primer - AV=1810 fps
17.0gr H110 - CCI-550 primer - AV=1826 fps

All those loads delivered groups just over 2" @100 yards which isn't all that bad from a levergun especially with my old eyes...

 

[Bruce51]

17.0gr Lil'Gun - CCI-550 primer - AV=1793 fps (that's amazing velocity!)

That sure is smoking hot!

I bet there was a bit of recoil with that load.

Thanks for sharing the info. When I run across some heavier bullets I will have to give them a try.

BLM

 

[Rule3]

Well in a 357 mag anyway..

Well that is what we are talking about so I do not understand you post?? It is required in other Mag loads also, In the 30 carbine you can use a small rifle. Does that cover it?

 

[ArchAngelCD]

17.0gr Lil'Gun - CCI-550 primer - AV=1793 fps (that's amazing velocity!)

That sure is smoking hot!

I bet there was a bit of recoil with that load.

Thanks for sharing the info. When I run across some heavier bullets I will have to give them a try.

BLM

Actually, not really heavier recoil. Lil'Gun was developed for 410 shotgun shells and then found a home with the .22 Hornet. When used in Magnum handgun shells it seems to generate high velocities without developing high pressures. The trade off, very high temperatures. I will not use Lil'Gun in .357 Magnum ammo meant for my handguns, only in my leverguns.

The velocities are higher and the pressures are much lower with Lil'Gun. I can't explain it but it's true... (especially with heavier bullets)