.357" 158 gr. XTP
Posted: Mon Oct 21, 2019 3:59 pm
I intended to test some snub loads in .357 in conjunction to a thread in the general section. Didn't know until Friday that my SP was a lucky dog who won a raffle on Thursday and brought along a brand new S&W 4" 686 Plus. That's as long as I'd want the barrel length to be for a 7-shot combat revolver.
Years ago he bought one of the early 7-shot Taurus Trackers which immediately had problems ejecting 125 gr JHP factory loads. I wasn't sure what to expect from the 686+. Luckily, I had a few of the WIN loaded 125 gr. JHPs that I had chrono'd previously at around 1475 FPS from a 4" GP-100 that seems to have a slightly faster bore. It ran a bit slower in the 686+ but the cases ejected easily and we ran some 140 gr. XTP handloads through it because I knew they were near Max Pressure. Again, they ejected easily.
I have one of the newer Accurate powders which is a version of W296 but has a flash suppressant added. That's 11 FS and after talking to Rob Behr up at Western Powder Co, his opinion is that it can be loaded using W296 data. I wish now I had chrono'd it from the 4" GP-100. I used ladder loads to get up to the Max Charge of 16.7 grs. Hodgdon shows the same charge for W296/H110 for the 158 gr. XTP, but from the 686+ it was a bit slow at 1123 FPS and seems pretty mild. CCI 550 primers were used. I did chrono that load from his 2 1/2" M66-4 to get 997 FPS. I water tested that load from the 4" 686+ and it performed pretty well. Shooting into 1-gallon water jugs I have found best penetration with a JHP reaching the 4th jug. This load went just barely out of the 4th but did not penetrate the 5th I decided to add for the first test.
It wasn't exactly easy to view the Flash characteristics, but from what I could tell, Flash was pretty mild. Nothing like W296/H110. The Lyman P&R III shows 17 grs to be their Max Charge and what I'll load next; that load will get chrono'd from the GP-100 as well as the 686. In older Lyman data, the 46th in this case, data is a bit warmer for the Hornady 158 gr. JHP that was the forerunner to the XTP. And as you might suspect, they went up to 17.7 grs of H110 with a pressure rating of 42,000 CUP.
For carry loads with low flash I tend to use faster burning powders like Accurate No 9, and No 7 can usually provide some pretty accurate loads at a bit less velocity. If all else fails, or barrel length is 3" or less, Ramshot True Blue is very hard to beat. But, if you have a 4 or 5" .357 Magnum for carry or as a field gun, 11FS shows good potential. From the GP100, based on other loads chrono'd, I'd expect the 16.7 gr. charge of 11FS to come in at around 1200 FPS. Some of you may already be aware that Alliant 300-MP was made for the same application. I have not tried it as yet. What I was actually trying to do was reach typical factory load velocity for 158s at say 1250 FPS, so more testing to come!
Years ago he bought one of the early 7-shot Taurus Trackers which immediately had problems ejecting 125 gr JHP factory loads. I wasn't sure what to expect from the 686+. Luckily, I had a few of the WIN loaded 125 gr. JHPs that I had chrono'd previously at around 1475 FPS from a 4" GP-100 that seems to have a slightly faster bore. It ran a bit slower in the 686+ but the cases ejected easily and we ran some 140 gr. XTP handloads through it because I knew they were near Max Pressure. Again, they ejected easily.
I have one of the newer Accurate powders which is a version of W296 but has a flash suppressant added. That's 11 FS and after talking to Rob Behr up at Western Powder Co, his opinion is that it can be loaded using W296 data. I wish now I had chrono'd it from the 4" GP-100. I used ladder loads to get up to the Max Charge of 16.7 grs. Hodgdon shows the same charge for W296/H110 for the 158 gr. XTP, but from the 686+ it was a bit slow at 1123 FPS and seems pretty mild. CCI 550 primers were used. I did chrono that load from his 2 1/2" M66-4 to get 997 FPS. I water tested that load from the 4" 686+ and it performed pretty well. Shooting into 1-gallon water jugs I have found best penetration with a JHP reaching the 4th jug. This load went just barely out of the 4th but did not penetrate the 5th I decided to add for the first test.
It wasn't exactly easy to view the Flash characteristics, but from what I could tell, Flash was pretty mild. Nothing like W296/H110. The Lyman P&R III shows 17 grs to be their Max Charge and what I'll load next; that load will get chrono'd from the GP-100 as well as the 686. In older Lyman data, the 46th in this case, data is a bit warmer for the Hornady 158 gr. JHP that was the forerunner to the XTP. And as you might suspect, they went up to 17.7 grs of H110 with a pressure rating of 42,000 CUP.
For carry loads with low flash I tend to use faster burning powders like Accurate No 9, and No 7 can usually provide some pretty accurate loads at a bit less velocity. If all else fails, or barrel length is 3" or less, Ramshot True Blue is very hard to beat. But, if you have a 4 or 5" .357 Magnum for carry or as a field gun, 11FS shows good potential. From the GP100, based on other loads chrono'd, I'd expect the 16.7 gr. charge of 11FS to come in at around 1200 FPS. Some of you may already be aware that Alliant 300-MP was made for the same application. I have not tried it as yet. What I was actually trying to do was reach typical factory load velocity for 158s at say 1250 FPS, so more testing to come!