357 sig WSF and 124gr RN by RMR

[Blue68f100]

CAUTION: The following post includes loading data that is not in any manual, aka wildcat load USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.

I was able to shoot some rounds over the crony this afternoon.
Gun used is Custom 1911 5" Kart Barrel in 357 sig
All crony data was collected at 5'
Brass used is RP of unknown source and some Speers range brass for 7.1 & 7.2.
Winchester SP primer used in all
Powder was Dispensed using a RCBS 1500 ChargeMaster and checked against a GP250. I allowed ±0.02 gr variation.
Max length of 1.140" used for these test.
I did a volume measurement to see what I had to work with, RMR 124gr HP @ 1.140" and came up with a internal volume of 0.74cc. This does not include the primer pocket. Just the space under the bullet.

My research showed very little data for the WSF powder. Published data is available for 147 gr bullet weight. With all of these I decided to start my load workup at 6.5 gr of WSF. Below is the crony numbers I came up with. I did not shoot for accuracy, have no sights on the gun. My dot sight has not come in yet.
5 shot average to determine my working range.

gr Avg ft/sec ES SD Comments
6.5 1257, 30, 11 Cold barrel
6.6 1255, 18, 7
6.7 1274, 16, 5
6.8 1288, 16, 6
6.9 1302, 34, 14 Don't know why these numbers (ES, SD) are out of line with the others.
7.0 1316, 25, 8
7.1 1341, 21, 7 Speers Brass, Primers starting to flatten, still have rounded edges, starting to get snappy. I would call this Max load since no velocity was gained at 7.2. but 7.2 had better ES & SD
7.2 1341, 8, 4 Speers Brass, Primers flattening but still have rounded edges. Snappy.
May be getting into +P loads some where around here.
I did test 7.3 and velocity jumped. Primers flattened but still had rounded edges on a few. every thing opened up.
7.3 1384, 52, 20 DO NOT LOAD. OVER PRESSURE, FLATTEN PRIMERS

This chart show the 7.1 & 7.2 running flat, no velocity gain. Remember shot groups of 5 on the chart starting at 6.5 gr



Will continue test once my dot sights come in to determine the most accurate load. Then on to 115gr XTP's.

 

[fxvr5]

Gun used is Custom 1911 5" Kart Barrel in 357 sig
All crony data was collected at 5'
Brass used is RP of unknown source and some Speers range brass for 7.1 & 7.2.
Winchester SP primer used in all
Max length of 1.140" used for these test.
I did a volume measurement to see what I had to work with, RMR 124gr RN @ 1.140" and came up with a internal volume of 0.74cc. This does not include the primer pocket. Just the space under the bullet.

My research showed very little data for the WSF powder. Published data is available for 147 gr bullet weight. With all of these I decided to start my load workup at 6.5 gr of WSF. Below is the crony numbers I came up with.
5 shot average to determine my working range.

gr Avg ft/sec ES SD Comments
6.5 1257, 30, 11 Cold barrel
6.6 1255, 18, 7
6.7 1274, 16, 5
6.8 1288, 16, 6
6.9 1302, 34, 14 Don't know why these numbers (ES, SD) are out of line with the others.
7.0 1316, 25, 8
7.1 1341, 21, 7 Speers Brass, Primers starting to flatten, still have rounded edges, starting to get snappy. I would call this Max load since no velocity was gained at 7.2. but 7.2 had better ES & SD By this logic 6.6 should be considered the max load.
7.2 1341, 8, 4 Speers Brass, Primers flattening but still have rounded edges. Snappy.
May be getting into +P loads some where around here.
I did test 7.3 and velocity jumped. Primers flattened but still had rounded edges on a few. every thing opened up.
7.3 1384, 52, 20 DO NOT LOAD. OVER PRESSURE, FLATTEN PRIMERS
This chart show the 7.1 & 7.2 running flat, no velocity gain. If speed had peaked it would not have increased with 7.3 grains. Your logic is flawed.

Hodgdon's 147 grain data shows their max load with WSF at 7.1 grains, and with only 33,800 psi. This is well short of the SIG's 40,000 psi limit. I doubt 7.1 with a 124 grain bullet will get you to max actual pressure.

 

[Blue68f100]

Yes but every gun setup is different. The jump in velocity from 7.1 & 7.2 to 7.3 was over double of what the standard was. At 7.1 the primers were flattening at 7.1, the recoil was getting sharp. At 7.3 they show indications of over pressure. Now I know that the Win SP primers are softer than CCI. So the only thing I have to go on is using the tools I have available. If someone with QL would be kind enough to run numbers it may give us a better understanding of what's going on.

 

[Mark_Mark]

I just recently bought a set of .357 Sig Dies! can’t wait to get the rest

 

[Warpiece]

Hodgdon's data looks really strange for the 147, almost like it was intended to be the starting load. Might want to try contacting them directly, the info may need correction

 

[Blue68f100]

Hodgdons show the 115 gr Bar Tac HP with a max of 7.4 gr WSF. So my finding are not that far off. The Hornady 147 gr XTP list a lot higher but that is normal, since most of the XTP are under size. I found 1 source on that said 7.1 was max for a 124gr. This powder may be a little fast, but too far out of line. I did find a load using W296/H110 with the 124gr bullets. It was like 10 -12 gr, that would be a fire ball.

I just recently bought a set of .357 Sig Dies! can’t wait to get the rest

The 357 sig can be a little tricky in setting up the seating/crimp die. I beveled the inside necks just to knock off the edge and nothing more. You can then seat the bullet without expanding, giving you max neck tension. In my testing I discovered it works best to do a light TC. This little bite helps prevent bullet setback during feeding. It also helped a lot on ES. I turned down a spare .355" PTX so it gave me 0.004-0.005" neck tension, so I could use my LNL-AP. Waiting on Starline brass to show up, have no idea when it will be processed.

 

[Mark_Mark]

Hodgdons show the 115 gr Bar Tac HP with a max of 7.4 gr WSF. So my finding are not that far off. The Hornady 147 gr XTP list a lot higher but that is normal, since most of the XTP are under size. I found 1 source on that said 7.1 was max for a 124gr. This powder may be a little fast, but too far out of line. I did find a load using W296/H110 with the 124gr bullets. It was like 10 -12 gr, that would be a fire ball.



The 357 sig can be a little tricky in setting up the seating/crimp die. I beveled the inside necks just to knock off the edge and nothing more. You can then seat the bullet without expanding, giving you max neck tension. In my testing I discovered it works best to do a light TC. This little bite helps prevent bullet setback during feeding. It also helped a lot on ES. I turned down a spare .355" PTX so it gave me 0.004-0.005" neck tension, so I could use my LNL-AP. Waiting on Starline brass to show up, have no idea when it will be processed.

thanks man. bottle necks are tricky to load. But, I like a challenge, they had factory startline brass at Sportsman, was ok in price!

 

[fxvr5]

The Hornady 147 gr XTP list a lot higher but that is normal, since most of the XTP are under size.

What does this mean? Undersize how?

 

[fxvr5]

Looking at Hodgdon's data I'd expect WSF to have a charge weight similar to, but slightly lower than, 572 in the 124 grain range. That would put it around a max of 8.0 grains for your bullet.

Ask Hodgdon for their suggestion.

 

[Blue68f100]

What does this mean? Undersize how?

Everyone I measure where about 0.0005" small. Hornady in general runs their XTP with a higher charge. This may be related to the jacket and core combo they use.

 

[fxvr5]

Everyone I measure where about 0.0005" small.

Not the ones I've measured.

 

[vaalpens]

How did you get a 124gr RN bullet loaded in 357sig with a 1.140" COL without the ogive being inside the neck of the case? Do you have a picture of one of your loaded rounds? Did you check/test this bullet/COL combination for setback?

 

[Blue68f100]

How did you get a 124gr RN bullet loaded in 357sig with a 1.140" COL without the ogive being inside the neck of the case? Do you have a picture of one of your loaded rounds? Did you check/test this bullet/COL combination for setback?

It took some time to locate where the ogive started. On the lot of bullets I have it goes away at 1.135", not a lot of wiggle room. I don't think I have any more loaded up. I know I have some 115gr XTP's to test but have not shot them yet.

I did a lot of testing on bullet set back. Drove me up a wall for while till I found the right setup. I did a change to my gun also. I install an elevated mag catch (+0.020"?) from EGW to raise the mag as high as possible. I had to relieve the bottom side of the extended ejector for clearance, just a little. I'm using Tripp Cobra magazines in my 1911. Without this I was getting as much as 0.020" setback. With this raised mag it can feed almost straight in, only 1 bump. Did some ramp work but kept the chamber fully supported. I believe Kart barrels uses a 35deg ramp on there 9mm. I had 1 short chambers for me to finish out sice he does not have 357 sig as a option.

Once I found the sweet spot I only needed to kiss the necks in (0.002-0.003") with the TC it pretty much stopped all of the setback I was getting. Without the TC I was getting 0.003-0.005" when chambering, some times larger. With this setup I can actually run a longer length 1.160" if I need too. When I cut the chamber I set it up to run bullets long if needed. I did not use the expander die that came with my Hornady 357 sig set. Like I said earlier I turned down a .355 PTX to 0.349". But the .349" is a taper to .340" so it starts easy but still retains a lot of neck tension. This ways it operates the powder dispenser without over expanding the necks. My press is still setup but I don't have any more clean brass to show a loaded round. I still have a dummy round I made, will take a photo but there is not much to see. Then only way to find the ogive start is with calipers or micrometer. Remember WSF is a pretty bulky powder, but I don't think it's a compressed load.

 

[vaalpens]

not a lot of wiggle room

True. There is not a lot of wiggle room with the 357sig. This is why I load only FP and JHP bullets. No RN for me.

I check the ogive with another case. Something like this:


If I can rotate the top case, then it tells me that the two mouths are touching and the ogive could be inside the neck. I try to not being able to rotate the case and have some gap, since not all cases are the same length. The true test is really the setback test.

 

[Blue68f100]

I don't know why I said RN, these are HP's . Will make the changes. Had a senior moment I guess. I've been using Berry's 124 gr RN in my 9mm.

Sorry for the confusion. I'm going to see if I have any 124gr RN that are suitable for the 357 sig.

 

[vaalpens]

I don't know why I said RN, these are HP's .

These are probably the RMR 124gr MPR JHP bullets. I load the MPR bullets with a COL of 1.125".

What are you trying to accomplish with your loads?

 

[Blue68f100]

These are RMR general purpose bullets. 9mm 124 Gr. RMR Jacketed Hollow Point (Multi Purpose Round) Bullets. I do need to order some of their Match winners when they get them back in stock. But these shot pretty well in my 9mm 1911.

I shot these with my 9 mm 1911 Kart 5" barrel, with a 2 moa dot sight. BE is 1", shot at 25yrds using bags. I cranked down the brightness of the dot so I could see the BE. For a general purpose bullet they shoot pretty good. My Berry's I have (124gr RN) , I'm lucky to get a 5" group.

 

[vaalpens]

BE is 1", shot at 25yrds using bags. I cranked down the brightness of the dot so I could see the BE.

You must have some good eyes to be able to focus on a 1" dot at 25yards through the glass of your red dot.

My Berry's I have (124gr RN) , I'm lucky to get a 5" group.

With the 357sig you should see better grouping. I don't do a lot of testing at 25 yards, but with my 357sig, I have been able to get groupings of 1.12", 1.215", and 1.64".

 

[Blue68f100]

You must have some good eyes to be able to focus on a 1" dot at 25yards through the glass of your red dot.

I struggle seeing a clean target at that distance. I was lucky to catch a cloudy day which made the dot show up easier. I have a bad astigmatism problem in my right eye which makes things worst. Regular sights are just a blur at any distance, that or my arms are too short. I need to get my eyes checked again, it's been almost 2 yrs since they been corrected.

My dot sights have glass lens vs plastic like most, gives a clearer undistorted view.. This was a new Holosun HS507C x2 dot sight. I switched over to manual brightness and adjusted it as low as I could and still see the dot on black.The 1911 I just finished the gun up a couple of weeks ago, from scratch build. Shown with the 357sig upper (above). As you notice I did not put a front sight on. The rear is a BoMar Adj Target sight with only the dovetail and adj screw cut. This locks the base it so it can not move. I did some more tweaking on the trigger last week.

 

[vaalpens]

I’m not sure if you can, but using a scope is much easier. I use a 2X scope and it helps a lot with my eyes since you have to focus on the scope. The red dot is better for every day use and defensive situations, but the scope is great for load testing.

 

[Blue68f100]

Have some more data to add. Here is some 115gr XTP and WSF, 6.8gr to 7.3gr at 1.135" OAL. 1" BE at 25 yrds with a 2 moa Holosun dot sight on my custom built 1911. I'm using a front rest and rear for my wrist. I have found that I can lock it down fairly well, but I see see lateral movement on the target. I'm finding I see the dot/target best during cloudy conditions. Bright sun make it hard for me to see the dot, since I have the brightness turned down. Crony data is on the target. All charges are measured using my GP250 scales. I shoot for the actual grain charge knowing that it gives me ±0.02gr accuracy.





Now for the 124gr has been a challenge. I'm not getting hardly any groups using the RMR 124gr HP (plated) bullet. Crony numbers look good (not great) and consistent but the bullets are not hitting the target. Groups start opening up above 1200 fps. I mean missing a full sheet of paper. I ended up shooting the 115gr load to confirm the dot sight was still zeroed. Going to revisit this once I get my brass order from Starline.

So I moved on to a New can of 50 yr old Herco. This powder worked good with the RMR 124gr RN bullets. These are a compressed charge, fills to the bottom of the necks.


I don't have any idea how I did this one. I'm not able to see the bullet holes while I'm shooting, only when I take the target down. Accidents happen. I slipped off the front rest as squeezed off the round, the low one.


I'm going to have to build a ransom type rest to get better data.