[Lightning]

I have been testing loads for my M&Ps this past week. Was thinking of switching to 147s from a 124 (FMJ). Anyway, I loaded some Star 147s with 3.2 grns of Clays. The load felt awesome. Soft, flat. However, it key-holed out of both of my M&Ps. So, I bought a box of Winchester 147s (White Box). They were a little more stout feeling than my handloads and a tad hotter - about 135 PF. They key-holed too. About 3 or 4 of every 10 rounds key-holed at 20 yds. So, I ordered 1000 147s from Atlanta Arms (the Team Glock Load). Wow! These were really soft and very consistent. The chrono'd at 128 PF with on a 6 fps standard deviation. Problem is, when I was testing for accuracy, 2 out of 10 rounds would key-hole at 20 yds. This is happening out of both of my M&Ps. I am stumped. Could it be the length of the barrel not being long enough to stabilize a heavy bullet? Has anyone else had these problems? Any ideas? Thanks.

 

[JBP55]

In my M&P 9 I have fired 147 in American Eagle, Lawman, WWB, Winchester JHP, Blazer, SXT, Ranger T,Black Talon and Reloads with no problems from 2-25 yards.

 

[YukonGlocker]

Mine doesn't keyhole with 147gr. either.

 

[Jetsurgeon]

I've got a M&P 9MM fullsize and shoot 147 Zero JHP's. Mine don't keyhole either, like the others. Maybe it's the bullets you're using.



Consulting my handload spreadsheet I've been working on for some time, I looked up the data for Zero 147 JHP, and Clay's UNIVERSAL powder. You're located in SC, I'm in NC so the elevation is about the same for both of us.



Zero 147 JHP - WSP - Mixed Cases - Clays UNIVERSAL 3.2gr - 1.135 C.O.L = 110.8 PF shot over a Chrono.



Winchester White Box chronographed with three different trips to the range at: 130.70 PF, 132.48 PF, and 131.0 PF.



Yea you are right, at 110.8 PF it is soft. But from my findings the accuracy with this load is ....... well crappy. LOL Shot off bags, at a measured 30 feet.



Hope this helps,

Jeff

.

 

[Lightning]

OK. I went out and did some more test today, after thoroughly cleaning both barrels. A friend pointed out that if the bullets were in fact keyholing and unstable, I would have a hard time getting them on paper at 25yds, not to mention getting them to group. He thinks its a matter of how the bullets are tearing the paper - appearing to keyhole. Seemed to make sense. So, I shot groups (freestyle) today at 25 and 35 yds. I got fist sized groups at 35 and 25yds with both reloads and Atlanta Arms JHPs. There were a couple of rounds that looked like the keyholed, but the groups were fairly consistent - given that I was shooting freestyle. I posted pix on the brianenos forums:



http://www.brianenos.com/forums/index.php?...mp;#entry586261



So, are they in fact keyholing or is it that the tears make it look that way?

 

[YukonGlocker]

I'm not signed up there, so I can't see the pics.

You should shoot into cardboard and see what happens.

 

[Lightning]

I'm not signed up there, so I can't see the pics.

You should shoot into cardboard and see what happens.

I am shooting at cardboard IPSC targets. Here are the pix:

 

[YukonGlocker]

They do appear to be key holing, but just slightly.



One of my favorite loads is:

147gr. XTP

3.3gr. TiteGroup

1.130" OAL



Although your groups look fine, you could also try a different bullet.

The Hornady XTP or Zero JHP would be good to try.

 

[YukonGlocker]

This is the most accurate load out of my M&P 9mm fullsize.

This load is scary accurate:

124gr. XTP

4.1gr. TiteGroup

1.120" OAL



I don't know what the PF is on this load. I intend to find out before long. It does have a little more recoil than the 147gr. load.

I have shot several 1.5" groups at 25 yards with this load. (Handheld off a bench.)



Also, I haven't tried messing with the OAL to see what happens. I think with some tuning, I could shoot 1" groups with this.

 

[Jetsurgeon]

Yukon,



Yea I agree on your scary accurate load posted above. My findings below:



M&P 9mm Full Size



Zero 125 JHP

Mixed Cases

WSP

4.1gr Titegroup

1.130 C.O.L.



5 Shots over the Chrono yielded an average PF of 126.5.



These were shot within the last month, 85 - 95 degree day temp, at aprox 380 ft above sea level.



Note that one low shot was probably me. All were shot from bags at a measured distance of 30'.



All the best!



Jeff

.

 

[243ww]

By far not an authority on ballistics but the shots do look like they are tumbling... In rifles the twist rate needs to be less for the heavier projies, more spin… Is it the same for pistols? What does the rifling look like in your barrel? Is it ok? :? :?:

 

[ncpilot]

Resurrecting this old thread...



I recently got the 9mm compact, and both today and last time at range got key holing. Very surprised... don't know if I've ever had it with any of my guns...



No problems with my full size--which I also shot today.



Using Rainier 124 RN with 5.5 Unique...



Is it possible the compact just doesn't have enough barrel length for heavier bullets?



I never did like Unique, but the new formulation is cleaner, and it is versatile. But it doesn't seem to be too accurate--and that's with shooting both guns today on a rest...

 

[choochboost]

Is it possible the compact just doesn't have enough barrel length for heavier bullets?

no

 

[sh0ck1999]

whats a key hole in terms of shooting? is the bullet tumbling and hitting the target sideways?

 

[YukonGlocker]

It's not necessarily tumbling. But the bullet isn't fully stabilized.

So it hits the target eccentrically.

 

[sh0ck1999]

what would cause this? unbalanced bullets or dirrty barrel with lead stuck in the rifling?

 

[shrek1974]

I have found the M&P9 doesn't really like plated bullets loaded over fast powders very well. I would say try a jacketed bullet like Zeros (when you can find them), or Montana Gold. A guy I used to shoot with shot a 147gr MG loaded with 3.6 of VV N320 at an OAL of 1.160" out of his M&P9. It was a pretty soft shooting load, but what was more impressive was that it would shoot into 3 - 4 inches at 50 yards very consistently.

 

[FixGuns]

The 147' skeyholing is a bit strange. The only thing I can think of is that maybe the bullet is too small for your bore. S&W rifling seems a bit shallow and if the bullet or some of the bullets are a bit undersize for your bore it may account for the intermittant keyholes. You might slug the bore and then check the bullets. Measure several to see if the sizing is consistant. It is the only thing I can thnk of that may cause this.