- Accuracy
- Velocity
- Muzzle Flash
- Barrel Length vs Velocity
Recently I picked up a Glock 27 as a new CCW gun.
So, I had to pick a good carry load for it.
The conventional wisdom is 'pick a premium factory load',
I like to cross-check with the chronograph, so I found
what loads I could, grabbed the chrono and headed down to the
indoor range. The loads I tested were:
Federal 180gr JHP
Remington 180gr Golden Saber
Speer Lawman 180gr TMJ
Federal 155gr Hydra-shok
Speer Gold Dot 155gr JHP
Winchester 155gr Silvertip
Cor-Bon 135gr JHP
.40 ammo is commonly available in 180gr, 165gr, 155gr and
a 135gr loading from Cor-Bon. The 165gr loadings are the
newest weight, and I didn't have any on hand to test.
When I get a good sample of 165gr loadings, I'll run them
through the chrono and see how they work. Note that several
of the factory 165gr loads are reduced velocity loads.
To get some more chronograph information, I took along a
Glock 23 and an STI Eagle 5.1, a full-size hicap 1911 in .40 S&W.
The Glock 23 is several years old and has probably 10 to 20
thousand rounds through it (lots of them were -Gasp!-
lead reloads) The STI has a few thousand rounds on it, and
the Glock 27 was new.
Barrel Lengths:
STI Eagle 5.1" (conventionally rifled)
Glock 23 4" (polygonal rifling)
Glock 27 3.5" (polygonal rifling)
The testing:
I clocked at least four rounds of each load through each
gun. Then I shot five rounds of each through the Glock 27
at 1" aiming pasters at 7 yards to check accuracy.
The leftover rounds I used for low-light flash testing in the G27.
- Accuracy:
At 7 yards, in the Glock 27, from a two-hand IPSC freestyle
hold. Accuracy figures are rounded to the nearest inch.
Federal 180gr JHP - 1"
Speer 180gr Lawman - 2"
Federal 155gr HydraShok - 1"
Speer 155gr Gold Dot - 2"
Winchester 155gr STHP - 2"
Cor-Bon 135gr JHP - 2"
At 25 yards, groups were around 3-4" from the G27.
- Velocity:
As expected, the shorter barrels produced less velocity.
Also as expected, most loadings in the same weight produced
about the same velocities. Overall, going from the 4"
Glock 23 to the 3.5" Glock 27 cost about 50 fps.
What I didn't expect was the performance of the 155gr Gold
Dot. This load had almost as much velocity in the G27's 3.5"
tube as the other 155gr's in the 5.1" barrel. In order to
verify this wasn't some kind of fluke, I got another box and
re-checked the velocities.
In the G27, this load beats everything else in both kinetic
energy (which favors light bullets) and momentum (which favors
heavy bullets). The only downside is it's muzzle-flash.
Still, it's my pick.
- Flash
After testing valocity and accuracy, it was time to turn off
the lights and check the loads to see how much muzzle-flash
each had in the Glock 27. The range was very dimly lit, and I
waited until I could make out a brown cardboard target at 10
yards before and between testing each load. With almost every
load, the flash was not bright enough to prevent me making
multiple rapid shots at the target.
Every load from the G27 showed a dark orange glow, usually
with a larger, quicker, and brighter yellow-white flash
superimposed on it. The orange glow is invisible in brighter
light.
The 'minimum muzzle-flash' champion was the 155gr Federal Hydra-
Shok. This load showed no flash besides the dull orange glow.
Winchester 155gr Silvertips were next lowest, although some older
loads (from a box a couple of years old) showed much more flash.
Both 180gr loadings also had fairly low flash.
The 155gr Gold Dot always had a bright yellow-white flash, and even
more so for the 135gr Cor-Bon. I checked these two loads in
the 5.1 and got minimal flash, so I assume the bright flash
is due to these loads using a slower-burning powder that isn't done
burning by the time the bullet exits the short barrel of the G27.
Even with these loads, and the dim light in the range, recovery time
from the extra flash was minimal for me. Total darkness and more
time for my eyes to adjust might change this.
- Chronograph Data
Chrono Data from Oehler 35P proof channel chrono
at about 8 feet. Temperature around 80'F.
Average of four shots per gun, except where noted.
Velocity (vel) is in feet per second.
Kinetic Energy (ke) is in foot-pounds.
Momentum (pf) is in IPSC power factor (velocity * weight in grains)
------------------------------
Federal 180 gr JHP
vel ke pf
Eagle 5.1 1005 404 180.9
G 23 962 370 173.2
G 27 913 333 164.4
------------------------------
Remington 180gr Golden Saber (sample size: 1/ea)
vel ke pf
Eagle 5.1 n/a n/a n/a
G 23 961 369 173.0
G 27 934 349 168.1
------------------------------
Speer Lawman 180gr TMJ
vel ke pf
Eagle 5.1 991 392 178.3
G 23 967 374 174.0
G 27 914 334 164.5
------------------------------
Federal 155gr Hydra-shok
vel ke pf
Eagle 5.1 1154 458 178.9
G 23 1107 422 171.6
G 27 1077 399 166.9
------------------------------
Speer Gold Dot 155gr JHP
vel ke pf
Eagle 5.1 1245 534 193.0
G 23 1210 504 187.6
G 27 1148 454 177.9 ***
------------------------------
Winchester 155gr Silvertip
vel ke pf
Eagle 5.1 1188 486 184.1
G 23 1131 440 175.3
G 27 1082 403 167.8
------------------------------
Cor-Bon 135 gr JHP
vel ke pf
Eagle 5.1 1335 535 180.3
G 23 1258 474 169.8
G 27 1210 439 163.4
(end article)