New load shoots high


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Peter_S
February 10, 2011, 02:52 PM
Yesterday I tried a new load; Hornady XTP 124 grain, 5.5 gr HS-6, 1.070"OAL.

After shooting a few practice magazines and hitting the target pretty consistantly I loaded the XTP reloads. They all hit 4 to 5 inches higher than my practice loads. (FWIW my practice rounds are 122 grain lead truncated cone, 4.1 gr W231, 1.015" OAL").

These were all shot from 6 yards.

Any suggestions why this would be?

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murf
February 10, 2011, 03:11 PM
hey peter s, i'm guessing more recoil from the xtp's. i'm also guessing ur shooting a 9mm. both loads are below the starting load listed in the hornady manual, so it's hard to say which load is going faster by the book.

murf

rcmodel
February 10, 2011, 03:14 PM
Yes, velocity and recoil differances in the two loads.

Your XTP load is below the recommended starting load in the Lyman manual.
It is only going a little over 900 FPS. HS-6 is slower burning then W231 also.

The lead bullet load is only 0.3 below MAX and is going over 1,200+ FPS.

The slower load gives the gun more time to recoil upward on target while the bullet is still in the barrel.

Bump up the XTP load to a more normal velocity level and the POI should come down.

rc

murf
February 10, 2011, 03:48 PM
what rc said about upping the velocity. the xtp has a lot of bearing surface compared to your 122gn lead bullet. with your current load you are running the risk of getting a bullet stuck in the bore. suggest using at least the minimum charge found in your reloading manual (for JACKETED bullets). good shooting.

murf

Peter_S
February 10, 2011, 04:03 PM
Thanks for the input rcmodel and murf.

My Lyman (47th) didn't really show a bullet close enough to the XTP that I was comfortable with but I found a couple of pages on the web copied from the Hornady manual. They show HS6 from 5.1 to 5.9gr with a OAL of 1.060". I increased the OAL a bit thinking I'd be safe using the mid load, but I guess the increased OAL dropped the pressure to the wimpy zone.

I'll try a few at 5.7 and 5.9 grains and see how they look.

Thanks again.

rcmodel
February 10, 2011, 04:50 PM
Lyman #49 shows a 125 Sierra & HS-6.
5.8 Start 949 FPS - 23,800 CUP
6.6 MAX = 1,080 FPS - 30,400 CUP.
Seated 1.075" OAL.

It is close enough to the 124 XTP shape you would be O.K. using that data.

rc

Peter_S
February 10, 2011, 05:35 PM
rc - that's good info. Without assuming any liability for what I decide, do you think I should be going a bit higher than the 5.7 grains I was considering to use next?

Maybe start with 5.8 and some at 6.0? Higher still? :D

rcmodel
February 11, 2011, 01:40 PM
I'd just load some at 6.0 and go see where it shoots.

rc

Peter_S
February 11, 2011, 03:06 PM
Roger that rc. I'll get some made up this weekend and take them out next week.

Again, thanks much for the help.

Peter_S
February 17, 2011, 09:51 AM
I shot ten of these yesterday - (124 grain XTP's with 6.0 grains HS-S). the increased powder brought them right into the black...they are great loads. As soon as my range does their "chrony-night" I'll measure some, but in the mean time I think they are good to go.

Thanks, I really appreciate your help.

MtnCreek
February 17, 2011, 10:07 AM
I load a Speer Gold Dot in 124gr at about the same length. With 6.6gr of HS6 I'm getting an avg vel of around 1150 fps from a full frame Glock. The Speer GD is very similar to your XTP. Just guessing, but I would think your
>1000fps at 6.0grs/HS6.

Peter_S
February 17, 2011, 03:57 PM
MtnCreek - what OAL are you at? I was using the Hornady data but could go longer. The 124 gr XTP is about 0.573" long. Is that close to the GD?

I was checking the cases from these and see no obvious signs of pressure so I guess I could still add a bit more powder. Thanks for the info.

MtnCreek
February 17, 2011, 05:24 PM
MtnCreek - what OAL are you at? I was using the Hornady data but could go longer. The 124 gr XTP is about 0.573" long. Is that close to the GD?

The data I'm using is from a Lee manual and they spec'ed a XTP; their info comes comes from the powder manufacturers. I'll do some measuring this evening and let you know. Either way, I think you're good to work up slowly.

Sunray
February 17, 2011, 06:44 PM
"...didn't really show a bullet close enough to the XTP..." Load for the bullet weight. Who made it doesn't matter.
The 125 grain jacketed data(the SIE FMJ data) on Hodgdon's site will do for a 124. One grain won't matter. Starting load of HS-6 is 6.4 grains. OAL is 1.090".
"...I'll try a few at..." Work up the load from the starting load. Don't just pick a few and hope.

MtnCreek
February 18, 2011, 09:20 AM
MtnCreek - what OAL are you at? I was using the Hornady data but could go longer. The 124 gr XTP is about 0.573" long. Is that close to the GD?

OAL is 1.08"., My GD measured .56", 6.6 gr of HS6 is giving avg vel = 1139 in G17.

I've loaded this projectile at this depth with up to 7.0 grs of HS6 with no issues. Please know that published data varies between 6.6 gr and 6.8 gr.

MtnCreek
February 18, 2011, 09:29 AM
"...didn't really show a bullet close enough to the XTP..." Load for the bullet weight. Who made it doesn't matter.
The 125 grain jacketed data(the SIE FMJ data) on Hodgdon's site will do for a 124. One grain won't matter. Starting load of HS-6 is 6.4 grains. OAL is 1.090".
"...I'll try a few at..." Work up the load from the starting load. Don't just pick a few and hope.

I'm not so sure that is always the case. If you load a FMJ Round Nose using Truncated Cone or Hollow Point Data, then you are seating the projectile 'deeper' than intended by the data; this has great potential to cause pressure issues. As long as you work up slowly and are mindful of pressure, it likely will not be an issue.

Also, if you load a Hollow Point in .45acp using FMJ Round Nose data, you may think the depth is just fine, until you try ejecting a live round from the chamber. Please don't ask me why I know this !

Peter_S
February 18, 2011, 11:09 AM
MtnCreek - Thanks for checking that. It's amazing that the Hornady handbook data maxes out at 5.9 grains HS-6 for the exact same bullet I am using. I started somewhere in the middle of their min/max but even that wasn't close. Oh well, live and learn.

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