155 Winchester STHP and old Double tap Chrono results [Archive] - Glock Talk

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ctkelly
05-25-2010, 16:40
Elevation 1155 ft above sea level. 89 degrees, 45% humidity. Chronograph 5ft from muzzle, CED M2 unit.

155 grain silvertip bullet, CCI 350 primers, starline brass new, 1.26 COL. Barrel is a KKM precision barrel, standard length for the G29.

10 grains of 800x

Had one error and forgot to record the ES, SD, etc.

AVG of the 5 shots was 1255 FPS.

no signs of overpressure clean burning

12 grains of AA #7

AVG 1206
ES 15
SD 5

Again no signs of overpressure, fairly mild load shot very nice. Clean burning

9.5 grains of Power Pistol

AVG 1315
ES 12
SD 4.0

No signs of overpressure, recoil was snappier than all other loads tested. Clean burning

And for some factory Double tap ammo....that was 5 years old. 200 XTP bullet, advertised at 1200 FPS from a G20....

AVG 1149
ES 28
SD 10.2

Hopefully I can get out and do some more testing, but I have a limited supply of these 155 STHP on hand.

preventec47
06-07-2010, 06:38
I am not familiar with the G29. What is the
std length barrel for that gun?

155gr is my favorite bullet weight in 10mm for
self defense

Since you used 12gr of AA#7 I thought you
might appreciate seeing that the load manuals
all list a higher max weight for that load.

Here is what the manuals say for 155gr MAX
loads but not specifically your bullets.

ACCURATE ARMS #7 & #9 Powder
155gr XTP 12.7 AA#7 (AA@7) 1379fps 37,500psi Accurate Arms 3.2.2
155 XTP 13.9gr AA#7 1400fps Hornady 4th edition
155 XTP 15.1gr AA#7 1450fps Hornady 7th edition pg 861
155gr Jkt Silvertip12.5gr AA#7 1324fps 29,800 CUP 2010 Lyman manual
155gr TMJ GDHP 13,0gr AA#7 1320fps CCI 300-350 Hornady Case, Speer #12 manual
155gr 15.9gr AA#9 1414 fps 32,700psi Accurate Arms manual 3.2.2
155gr Jkt Silvertip 15.5gr AA#9 1343fps 27,900 CUP 2010 Lyman Manual
155gr 13,0 AA#7 1320fps CCI 300-350 Speer #12 manual

> Hodgdon manual-------------------------
> 135gr Autocomp 9.5gr 1476fps 34,500 psi is a Winchester powder
> 155gr Autocomp 8.9gr 1362fps 35,700 psi is a Winchester powder
> 155gr IMR 800-X 9.8gr 1350fps 30,000 psi

A snapshot of an old IMR load manual page ( date unknown) shows
155gr Rem JHP Rem 2 primer 11.6gr 800X 1475fps 32,900psi 5” barrel


> Alliant Data---------------
150JHP 9.7gr Power Pistol 1415 fps fed 150 primers 1996 manual
155 JHP 11.5gr Blue Dot 1340 fps Fed 150 primers 1996 manual
155 XTP 12.7 Blue Dot 1350 fps Hornady 4th edition
155 XTP 12,9 BlueDot 1450fps Hornady 7th edition manual
155 Speer GDHP 12gr Blue-Dot 1291 fps 2010 Alliant website



10mm Bullet Lengths------------------

Nosler 150 JHP .535 “

Hornady 155 XTP .555 “

XTREME (solid double plated) 155gr .512 inch

ctkelly
06-07-2010, 11:05
3.78" is the standard length for a G29.

I did not have access to loading data for the 155 Silvertip specifically so I started low. It is ill advised to take load data from 155 to a different bullet brand and expect it to work okay....For one example, the base on a silvertip is flat....the base on a GDHP is dished and in theory could handle more powder behind it. Further more I am willing to bet none of those manuals are using the CCI 350 MAGNUM pistol primer either which adds in another variable to testing.

I have advanced to 12.5 and 13.0 grains of AA#7 behind the silvertip and will chronograph as soon as the weather cooperates with me. I also have some 155 GDHP loaded with 10.3 of IMR 800x which was one of Mike McNetts most accurate loads according to him. And lastly, 10.5/11.0 grns of aa #7 behind the nosler 180 JHP. All of these are ignited with a 350 CCI primer and the GDHP/NOSLER loads will be using my new top brass I picked up from scharch.com.....it on averaged weighed 4 grains more than the starline.....should be interesting.

preventec47
06-07-2010, 15:16
Thanks very much for your detailed and objective reports
that we can all learn from.

It is why we are all here.
To share what we have learned the hard way and to
more easily learn from others what they have learned
the hard way.