357 Magnum to Maximum

[togojeff]

Just recently reamed my handi to 357 maxi thanks to a fellow board member

I have 140 and 158 gr Hornady XTP's on hand that I'd like to try loading.
I also have some lyman 358156 gc bullets cast from wheel weights that I
could use.
The 140's would strictly be for target and varmints. Also I only have W296
and IMR 4227
for powder at the moment. Powder selection and availability in this part
of the world are limited right now. Any recipes would be appreciated.

[oldsoldja]

how much did you have to ream? will you still shoot mags in it?

[dpe.ahoy]

W 296 and H 110 are the same powder and both are good in the Max.  Since you have a computer, go to the Hodgdon web site and get their recommendation for charge weights.  Accurate 1680 is also a good powder for the Max, and the recommendation from them for the 158gr is a start load of 23.9 and max load of 26.5 gr.  I got that from the Ballistician at Western Powder who is the distributor for Accurate powders.  They also distribute the Ramshot powders and are located in Miles City, MT.  The mans name is Johan Loubser, and his e-mail is johan@ramshot.com.  DP

[Lon371]

 Here is what Hodgdon says
http://data.hodgdon.com/cartridge_load.asp

Reloadammo.com
http://www.reloadammo.com/357max.htm

Lonny

[quickdtoo]

how much did you have to ream? will you still shoot mags in it?

See the 357 Maximum reamer sticky and the FAQs link on the same topic.

Tim

[togojeff]

Thanks for the info guys. I had already checked the Hodgdons site
and I thought the loads on the Hodgdons site were pistol loads.
Or should I just use them as a starting point?

[quickdtoo]

I doubt you'll find specific Maximum rifle data, just pistol.

Tim

www.357maximum.com

http://www.accuratepowder.com/data/PerCaliber2Guide/Handgun/Standarddata/35738Cal(9.2mm)/357%20Remington%20Maximum%20page%20105.pdf

[petemi]

Here's an article on the maxi out of a 21" contender carbine.  Pretty close to our 22 inch.  Enjoy

Pete

http://www.ottllc.com/specialtypistols/sp10.html

[togojeff]

Thanks Pete and Tim for the links.

Anyone care to share their pet loads for the maxi?

PM me if you don't want to post publicly.

[aromakr]

I shoot heavy bullets in my maximum, and found it really likes H1680. I spoke to the ballistics people at accurate. They tell me A1680 is on the verge of being too slow for that case, so I should not have a problem with high pressures 40,000 c.u.p. or under in a compressed load. This is exactly what I found. Maximum recommended load is 25.5 grs with 180 gr speer with win 6 1/2 primers & Remington cases. I've gone as high as 28 grains with no pressure signs, however my best accuracy was 27.4 grs which was right at 1". I had a max velocity spread of 13 fps with that loading. Primers showed normal pressure and the cases all but fell out of the chamber. NOW I'M IN NO WAY RECOMMENDING THAT ANYONE TRY THIS LOAD AS IT IS WAY OVER MAX, DO AS YOU FEEL IS SAFE FOR YOU.
Bob

[Badnews Bob]

Mine shoots best with 180gr bullets, I use 180gr LBT LWFNGCs 21 grs of IMR4227 or equivalent load of AA1680 seam to be the sweet spot.

[togojeff]

Thanks Bob and Bob

Just fired my 357 maxi conversion for the first time today.
Groups were good- 2 inches at 100 yds and 4 inches at 150 yds-minute of coyote.
This was with 140 gr XTP's, so I am sure with heavier bullets, the groups will tighten
up. I'm also using a cheap pellet gun scope so improvements can be gained there
as well.

One thing though, I may have overpressure problems with this load:



These are the first abnormal looking primers I have seen on my handloads.

Load specs are 140 grain XTP's over 23 grains of W296 with a COL of 1.890"
Winchester small rifle primers were used and the bullets are lightly crimped.
Also the cases were sooty which is usually a sign of low pressure if I am correct.

As you can also see the 357 mag cases look fine. They also grouped well at 2 inches.

Could the fact that I have the Sb1 receiver have something to do with this?

[clearwater]

Thanks Bob and Bob

Just fired my 357 maxi conversion for the first time today.
Groups were good- 2 inches at 100 yds and 4 inches at 150 yds-minute of coyote.
This was with 140 gr XTP's, so I am sure with heavier bullets, the groups will tighten
up. I'm also using a cheap pellet gun scope so improvements can be gained there
as well.

One thing though, I may have overpressure problems with this load:




These are the first abnormal looking primers I have seen on my handloads.

Load specs are 140 grain XTP's over 23 grains of W296 with a COL of 1.890"
Winchester small rifle primers were used and the bullets are lightly crimped.
Also the cases were sooty which is usually a sign of low pressure if I am correct.

As you can also see the 357 mag cases look fine. They also grouped well at 2 inches.

Could the fact that I have the Sb1 receiver have something to do with this?

Firing pin problem maybe?

Check the other thread on sb1 and maxi.

[OR-E-Gun Bill]

These are the 1st three fired from my recently reamed SB1 .357 Mag to Max.
Can't see any problems with the primers at all. They look the same as the .357 Mag. that have been fired.
Loaded with Sierra 158 gr. Sportsmaster JHC
R-P brass
17 gr. H-110
CCI-450 Primers
Heavy Crimp



Bill

[aromakr]

Jeff:
I had sooty cases with the A1680 also until I got to 26.5 or 27 grains then the soot was reduced substantially but not eliminated.
Your primers an really cratered, looks like the pressure is getting high with that powder. The fireing pin in a handi is not like a bolt gun and primers will flow into the pin hole quite easily.
You know a pellet gun scope will not last long on cartridge rifle, they are designed for the forward recoil of an air rifle and not the rearward recoil of a regular gun. you will shoot the crosshairs loose.
Bob

[gcrank1]

No downside to trying a different brand of primer (CCIs are said to be tougher) and see what you get.
Id say you are close to finding the right balance, just try out the variables a bit.

[togojeff]

I have some CCI primers, will give them a try next and see what happens.

And a new scope is on the want list for sure.

[togojeff]

These are the 1st three fired from my recently reamed SB1 .357 Mag to Max.
Can't see any problems with the primers at all. They look the same as the .357 Mag. that have been fired.
Loaded with Sierra 158 gr. Sportsmaster JHC
R-P brass
17 gr. H-110
CCI-450 Primers
Heavy Crimp


Bill

That is definitely a light load Bill. In the Hornady 7th edition that is below starting.

[wreckhog]

Light loads (<90%) of H110/W296 are known to create HIGH pressure issues.

[OR-E-Gun Bill]

That is definitely a light load Bill. In the Hornady 7th edition that is below starting.

Lyman 49th has it as a Suggested Starting Load for T/C Contender w/ 10" & 14" barrels using standard small rifle primers.

Bill

[togojeff]

Well I tried CCI primers with the same load and no difference:





I did find a little more accurate combo though with 21 grains of IMR  4227 under
158 grain Sierra sports masters


For those of you still in an Olympic frame of mind:


Same thing again on the primers though:



I tried a 3 shot group with 158 gr XTP's over 21 grains of IMR 4227 and got a 6 inch vertical string
and I mean vertical:


I think with a little tweaking and a better scope I can get a 1" MOA group with the Sierras
The heck with the funny looking primers, I can live with that.

[aromakr]

Jeff:
You know re-looking at those primers, its not really showing pressure signs. The outside edge of the primer is still rounded not flat too the primer pocket. High pressure signs will have a completely flat primer with the cup at the firing pin hole. I think you might just have a pin that is smaller than the hole. Are they extracting easily?
Bob

[togojeff]

Jeff:
You know re-looking at those primers, its not really showing pressure signs. The outside edge of the primer is still rounded not flat too the primer pocket. High pressure signs will have a completely flat primer with the cup at the firing pin hole. I think you might just have a pin that is smaller than the hole. Are they extracting easily?
Bob

No problem with extraction whatsoever.

[togojeff]

Call me an idjit, upon closer examination using calipers I think I have found the problem.
When I reamed the chamber I went a tad too far. The case sits in the chamber
.008" deeper than flush. I thought I had stopped in time

Funny thing is the fired .357 mag cases don't display the same primer results, they
are normal.

The load is 18.1 grains of W296 under 140 XTP's, so it is no wimpy load.

[quickdtoo]

There's an easy solution to that problem Jeff. 

Tim

Have the barrel replaced by H&R if it's factory fitted, the other method is to modify the extractor to hold the round against the breech face, you have to thin the post on the breech face side a little, then place a shim on the front side of the post so it bottoms out in the extractor slot under the chamber, the post must be thinned a little to do that first tho, when finished it will hold the round flush with the chamber face.

Tim

[togojeff]

There's an easy solution to that problem Jeff. 

Tim

Have the barrel replaced by H&R if it's factory fitted, the other method is to modify the extractor to hold the round against the breech face, you have to thin the post on the breech face side a little, then place a shim on the front side of the post so it bottoms out in the extractor slot under the chamber, the post must be thinned a little to do that first tho, when finished it will hold the round flush with the chamber face.

Tim

Is there anyway I can screw that up? Never thought I would mess up the reamer job.

[quickdtoo]

Not permanently, you can either remove the shim or order a new extractor from H&R as a last resort. I've used epoxy, let it cure, then file it to provide zero headspace, aluminum furnace tape works for a temp shim to try it out, then you can make a more permanent fix. The only changes are made to the extractor, not the barrel.

Tim

[cwlongshot]

Hello,
 I just finished reading thru all the posts and have a number of questions...

1) You mention you just reamed it in the first post... (A) Was it a used barrel that you fit, or (B) a complete gun with a factory fit barrel OR (C) a complete gun that your unsure of its history.

2) Your cratered primers are not necessarily a sign of too high a pressure. If your frame is a SB1 shotgun frame with a large firing pin. That's why your experiencing the primer flow back around the pin.

3) You have switched to CCI with the same results, but what kind of primers are you using? Small Rifle or Small Pistol? I use STD small rifle CCI and Match Remington SR primers.

4) Measuring pressure by looking at primers alone isn't accurate. Measure the cases web just above the rim where the brass thins to form the case walls, tells a truer story. You say after firing, the case falls out of the chamber, so its very likely your loads are on the lighter side. Even so, as others have said, your primers are still very round at the edges...

I have had my best accuracy with AA1680 powder and Hornadys 180SSP bullet seated and crimped in the cannalure, sparked with a Small Rifle CCI primer.

CW

[Badnews Bob]

Put some 180 gr XTPs on top of that 21grs Of IMR4227 and see what ya get.

[togojeff]

CW This is a factory fitted barrel and all the primers are small rifle.
Tim I will work on that extractor when I get home from work, don't have the
materials here that I need.
Will it do any harm to fire it in the meantime?