147 gr JHP 9mm COAL Question

I recently rebuilt a new 9 mm SA RO with a 1:10 barrel. Doing a seating depth test, contacting the rifling, the maximum COAL with the 147 XTP is 1.165", but with the Zero 147 JHP it is 1.230", and Magnus 147 JHP roughly the same at 1.235". The latter two could, say, produce a round that is beyond the 1.169" max COAL for a 9 mm. Curious if anyone has experience loading the 9 mm 147 gr Zero or Magnus JHPs in the 1.220 - 1.225 range through a 1:10 barrel? What, if any, loads gave good accuracy and cycling? I'm curious if loading long and decreasing the jump was of any benefit with those two bullets, when loaded soft and subsonic. At those lengths, there is still plenty of bullet below the case neck (its a tapered case anyway). I have a 38 Super magazine for testing, and the barrel has the Wilson/Nowlin ramp. In the past I have had good accuracy in a 9 mm 1:10 barrel and the 147 XTP (Sig P210A), but I'm wondering if that was because to some extent they were never jumped more than about 0.010".

Bullet jump in 9mm is your friend!
Jon

Jon Eulette wrote:Bullet jump in 9mm is your friend!
Jon

That is a extremely interesting statement. I'm currently loading for USPSA competition. 
Without imposing too much could you expound on this?

walt k wrote:

Jon Eulette wrote:Bullet jump in 9mm is your friend!
Jon

That is a extremely interesting statement. I'm currently loading for USPSA competition. 
Without imposing too much could you expound on this?

I had heard that some of the action shooters were loading long to enable an increased power factor in 9 mm...but their 50 yd accuracy requirements are not Bullseye. So I was wondering if anyone did some controlled testing.

I DID A LOT OF 9MM RR TESTING. I'VE SHOT ROCK RIVER 9MM's (PPC AND BULLSEYE), KIDD BERETTA, SAMS BERETTA, S&W PPC9 AND A FEW OTHER BUILDS.

THE BEST OAL FOR ACCURACY I GOT CAME RIGHT OUT OF THE VV  LOADING DATA. 1.142" IN 115,121,124,125 & 147 BULLET WEIGHTS. THIS WAS WITH HORNADY XTP JHP. THE 121 AND 125GR WERE THE HORNADY HAP BULLETS. THE 121HAP IS A GREAT BULLET. BUT ONLY AVAILABLE TO COMMERCIAL LOADERS IN 3K ROUND BULK RATE BOXES NOW.

RATE OF TWIST WERE 1/10, 1/16, 1/17.5(PPC9)& 1/32

tovaert wrote:

walt k wrote:

Jon Eulette wrote:Bullet jump in 9mm is your friend!
Jon

That is a extremely interesting statement. I'm currently loading for USPSA competition. 
Without imposing too much could you expound on this?

I had heard that some of the action shooters were loading long to enable an increased power factor in 9 mm...but their 50 yd accuracy requirements are not Bullseye. So I was wondering if anyone did some controlled testing.

Why would anyone load long to increase power? That would decrease chamber pressure and lower power. Just curious . .

The reason I asked about the jump was because I load for my CZ Shadow 2 with a C.O.A.L. of 1.095- 1.100 which shot well in my Sig X-5 Legion which has a C.O.A.L. of 1.160.

LenV, they load long so they can cram even more powder in the case. Look up some of the 9 mm Major loads if you get the chance.

I was not planning on stuffing a lot more powder in the case...just loading long to perhaps mimic a softer shooting 38 special-like round and eliminate the characteristic 9 mm "snap," if that's possible, without losing the 50 yd accuracy. I would like to keep the MV under 900 fps. I can't load the XTP "long" due to the nose profile, since I'm assuming it's not a good idea to jam a 147 XTP 147 into the rifling, but loading long can be done with the 147 Zero and Magnus. Before Ransom testing and burning primers I thought I'd ask about others' experiences. But it's not worth it if I going down some rabbit hole. I really want a 1911 in 38 sp but I'm trying to resist that temptation for now.

CR10X wrote:LenV,  they load long so they can cram even more powder in the case.  Look up some of the 9 mm Major loads if you get the chance.

Some can be found here:

https://www.ssusa.org/articles/2018/1/9/how-to-use-9-major-in-a-short-barrel/

The SSUSA article was interesting. All rounds tested, however, were at 1.150" COAL, well within SAAMI for 9mm. I don't consider that loading "long." But they were looking for crazy high MVs well beyond what I'm looking for, but I understand why they want those speeds. 25 yard accuracy was pretty crappy, but I'm not surprised. I would like them to group around 1-1/2" to 2" at 50 yards at ~800 fps MV. 25 yards then takes care of itself.  

I'm going to try out to ~1.215" (Zero and Magnus 147 JHPs), fired from a 38 super magazine. Will get back here with results. Today it hit 75 degrees! But of course winds were gusting to 35 mph.