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135 Grain Shootout with Glock 27


This is the first in an evaluation series on premium defense loads fired from the Glock Model 27. The 27 is a .40 S&W pistol and five loads are the subject of this evaluation. Only one load “profile” will be tested for each series and this first series will look at the 135 grain loadings. This testing came about as a result of several things, most important to me was to choose a defense load for myself. Additionally, I have found that most people do not have the time, equipment, or techniques to conduct a thorough evaluation for themselves and we are just expected to believe what the manufacturers tell us. Every manufacturer has the “ultimate” bullet, or the best stopping power, but how do we know the difference between performance and marketing? Most people concerned with the defensive use of a handgun are fairly demanding of their ammunition and equipment and many people wanted to have more information on which to base their decisions on ammo selection. The precipitating events were the result of some conversations with the ammunition manufacturers and some offers of free ammunition by some of these companies to members of a website for Glock enthusiasts.


Five companies, from small to large, were found to offer a 135 grain loading in a self-defense loading in .40 S&W. They are Cor-Bon, Federal, Gray Area, Pro-Load, and Triton. In the tests, this alphabetical order will be used and it implies nothing else. Some you may have heard of, others maybe not. All five companies provided at least 120 rounds of ammunition necessary to complete the test protocol. Triton also provided the ballistic gelatin for the testing.

One box of ammunition was procured from sources other than directly from the manufacturer in order to ensure that the provided loads were consistent with what can be purchased off the shelf. This “purchased” ammunition will serve as a “proof” load during the test protocol and will not be mentioned unless a significant deviation from the provided ammunition is found. This was done more to quell hecklers that might scream foul when their favorite load does not perform as they thought it would.

Each test will rank the ammunition from first to fifth. At the culmination, a final ordering of the five rounds will be presented. A full text version of the testing including data will be available in some format at the culmination of the testing.

TEST #1 -- Packaging/Appeal

This involves a lot of opinion, but accounted for the overall appeal of the packaging and the loaded rounds as well as any potential "legal" ramifications.

Cor-Bon: 4th

Federal Personal Defense Hydro-Shock (PDHS): 1st

Gray Area: 5th

Pro-Load: 2nd

Triton Hi-Vel (HV): 3rd

Except for Cor-Bon which used standard brass, all of the loads used nickel plated cases. This helps significantly in the appeal of the rounds but also increases reliability and corrosion resistance.

TEST #2 -- Weights and Measures

This test is kind of like the “Quality Control” portion. Five cartridges, all from the same lot were randomly selected and then weighed and measured. From the purchased box of ammo, the lightest and heaviest total weight cartridge was also weighed and measured. If the weighed difference of any one component was out of the range of the 5 sample cartridges, it is reported. The criteria here is not the actual weights and measures, but consistency. We are dealing with premium ammunition demanding premium prices and only the best will do. Consistency is what is necessary for accuracy and reliability. However, some dimensions will affect function and reliability and those were looked at as well. Following the place, the numbers are the spread of the Case Overall length in inches, and the spread of the powder charge in grains. Several other measurements were taken and account for the socres, but these are two of the most critical measurements.

Cor-Bon: SCORE = 37.4%, 5th [0.0057, 0.8]

Federal: SCORE = 63.6%, 3rd [0.0050, 0.4]

Gray Area: SCORE = 59.2%, 4th [0.0037, 0.5]

Pro-Load: SCORE = 85.4%, 2nd [0.0013, 0.2]

Triton: SCORE = 86.0%, 1st [0.0018. 0.1]

TEST #3 -- Muzzle Flash

Muzzle flash is important in a defense loading primarily because the majority of police and citizen self-defense shootings occur in low light situations. The ability to see your sights, asses effect of previous shots, and look for other threats and avenues of retreat may be greatly compromised by high flash loads. The five loads are simply ranked from lowest flash to highest flash.

Cor-Bon: 4th

Federal: 3rd

Gray Area: 2nd

Pro-Load: 1st

Triton: 5th*

The differences between 1st through 3rd was very small and I asked several folks for their opinions before I gave the final rankings. 4th was also pretty close and 1st through 4th offered little or no distraction during night shooting with a dull orange flash. 5th was just a bright white flash and is enough to make me be very leery of using this load for defensive use.

The video clips have two shots each, one of which was the brightest for the load. The video was shot from the side, but the rankings are from the shooters perspective and the very low recoil of the Federal load may have allowed the shooters to see more of the flash than with the Pro-Load and Gray Area since the gun was in the way with these higher recoiling rounds. There were a few higher flash rounds encountered at the indoor range session with the Federal as well.

*Triton changed their powder to reduce flash after the tests were started. On December 22, 1999, I shot some 135 grain Triton with the new powder. While it did reduce the flash from about basketball size to softball size, it still had the highest flash of the 5 loads. The flash was still a bright white flash, but not blinding in low light as with the original powder. Also, the primers were flattened with the new powder indicating higher pressures. This does concern me.

CORBON: Click photo to download an MPEG showing muzzle flash with Corbon ammo

FEDERAL: Click photo to download an MPEG showing muzzle flash with Federal ammo

GRAY AREA: Click the picture to download an MPEG showing muzzle flash with Gray Area ammo

PROLOAD: Click the picture to download an MPEG showing muzzle flash with Proload ammo

TRITON: Click the picture to download an MPEG showing muzzle flash with Triton ammo

TEST #4 -- Recoil

Felt recoil is somewhat subjective as it matters how the shooter perceives and reacts to recoil. Is the load designed to minimize the felt recoil or is it even considered by the manufacturer? If recoil was not an issue, there would certainly be a lot less 9mms in circulation. Recoil affects the shooter mentally and physically and does impact shot placement and speed.

Recoil was evaluated in several different ways; muzzle flip, felt primary and secondary recoil impulses, time to follow-up shots in multi-shot strings and accompanying accuracy. All of the factors went into determining the load with the least recoil. The lightest recoiling load also has the lowest velocity. Group 3 size, which was 5 rounds at 7 yards rapid fire, from the accuracy testing and corrected time is presented for each round. The group was fired as fast as possible once the sights settled.

Cor-Bon: 5th (20.7 cm in 3.66 sec.)

Federal: 1st (6.9 cm in 2.01 sec.)

Gray Area: 3rd (20.1 cm in 3.22 sec.)

Pro-Load: 2nd (11.1 cm in 2.09 sec.)

Triton: 4th (18.5 cm in 3.35 sec.)

Group 3 had originally been slated for 10 rounds but the 4th and 5th place loads could not be fired for more than 5 rounds in the G27 without regripping. The 1st through 3rd place loads could fire 10 rounds rapid fire without re-gripping.

TEST #5 -- Noise Level

Flash is being considered more and more in defense loadings, but one area often overlooked that has similar issues, is noise level. An officer or legally armed citizen will not be walking around with ear muffs on nor will he have time to put them on in a deadly encounter. The noise level was measured and all exceeded OSHA specs (big surprise) but there were definite differences. As I was not willing to sacrifice my own ears for the test, only the first place load was fired, one time outside, without ear protection. There was no discomfort or perceptible hearing loss.

Cor-Bon: 4th

Federal: 1st

Gray Area: 3rd

Pro-Load: 2nd

Triton: 5th

4th and 5th place had significantly more noise than the other 3 loads. Firing these loads without hearing protection would most definitely result in hearing damage.

TEST #6 -- Velocity

This is most often considered THE test for defensive handgun ammunition. But, I hope by now that you will understand that many factors are involved in evaluating premium defense ammunition. Velocity IS NOT the end all for handgun ammunition. For a 135 grain loading, 1100 fps seemed to be about the lowest velocity that I would consider capable considering the round. But we must also realize that 100 fps is really of little consequence between the various brands. What is important is how that velocity affects performance and terminal ballistics and the pressures and recoil associated with that velocity. In essence, in this test, I am again looking for consistency. Small extreme spreads are the most important. Statistical evaluation is valid, but considering only a few rounds will be fired in a shooting situation, the luxury of large test populations and standard deviations is hardly a good measure. The pistol was cleaned between loads and 2 fouling rounds were fired prior to the test and the rounds were then fired at approximately 5 second intervals. 10 rounds of each load were fired over the chronograph plus 2 rounds from the purchased ammunition. All of the bought "proof" loads fell within the tested range. Following the score are three numbers which are average velocity, standard deviation, and extreme spread all in feet per second. Due to popular demand, I have added the advertised velocity of each load. They are nominally from 4" barrels and so don't get too bent out of shape that the loads don't make the advertised speed from the short barreled G27.

Cor-Bon: 5th

Ave.=1287.4, SD=30.1, ES=109, Advertised @ 1325

Federal: 4th

Ave.=1154.3, SD=18.9, ES=72, Advertised @ 1190

Gray Area: 1st

Ave.=1265.4, SD=12.2, ES=40, Advertised @ 1300

Pro-Load: 2nd

Ave.=1218.0, SD=13.1, ES=48, Advertised @ 1260

Triton: 3rd

Ave.=1212.3, SD=15.3, ES=57, Advertised @ 1325

TEST #7 -- Accuracy

Accuracy goes back to consistency. The most consistent rounds should have the best accuracy one would think, but don't bet on it. Is accuracy important? Yes, but again, it is not the most important factor. I will consider any round which is capable of placing 5 rounds in 5" at 7 yards as acceptable and all the loads were well under that mark. Since several different accuracy tests were used, this test will again use a score for placement. There are 3 groups and each group was worth 10 points for 30 points total. Additionally, the smallest MOA for the various tests will be reported (MOA=Minute of Angle, 1 MOA is approximately 1" at 100 yards). I should also note that these three groups were fired offhand without rests. We can also agree that the sights on the G27 are not exactly set-up for accuracy work. But, this would be how a defensive weapon is fired so it is valid for these tests. I did shoot my tailored handload along side of the test loads and its groups were better than any of the test loads. For comparison purposes, its best MOA was 6.9.

Cor-Bon: 3rd, SCORE:47%, 21.3 MOA

Federal: 2nd, SCORE: 87%, 14.6 MOA

Gray Area: 4th, SCORE: 40%, 26.4 MOA

Pro-Load: 1st, SCORE: 93%, 13.6 MOA

Triton: 5th, SCORE: 33%, 36.8 MOA

TEST #8 -- Pressure

Pretty self explanatory. If the round is over SAAMI max for the .40 S&W cartridge, it fails. Scored only as Pass or Fail. A fail gets 5th place points in the final standings and a pass gets first place points.

Cor-Bon: PASS

Federal: PASS

Gray Area: PASS

Pro-Load: PASS

Triton: PASS

Although the case and primer material have an impact on the amount of deformation experienced during firing, the following observations are noted.

Cor-Bon had flattened primers and deep firing pin marks on the primer. The case base diameter increased by 0.015" when fired.

Federal had no flattened primers and normal firing pin marks on the primer. The case base diameter increased by 0.007" when fired.

Gray Area had slightly flattened primers and slightly deeper than normal firing pin marks on the primer. The case base diameter increased by 0.010" when fired.

Pro-Load had no flattened primers and normal firing pin marks on the primer. The case base diameter increased by 0.007" when fired.

Triton had slightly flattened primers and deep firing pin marks on the primer. The case base diameter increased by 0.011" when fired. When shooting the load with the new powder, the primers had completely filled in the primer pocket edges indicating increased pressures and the firing pin pierced a few of the primers and left significant marks on others. The new powder loads had the case diameter increase by 0.015" when fired.

TEST #9 -- Media Testing

This may be one of the more important tests. But there are a lot of factors thrown into this test and some subjective judgement as well. None of the cartridges were designed to break-up so retained weight and expansion will be evaluated. The tests include ballistic gelatin covered with denim as is industry standard, waste animal tissue, a slurry of fluid and solids in which penetration can be measured.

I am finished with the media tests, 160 rounds total were fired into media! The rounds were fired into drywall, plywood, elk tissues, covered and uncovered gelatin, a glycerin/newsprint slurry (a doctor suggested this one to me) and water. The Pro-Load and Gray area were fairly similar in performance with good penetration (over 12 inches every time in all media) and weight retention (over 95%). The Federal also did well in weight retention, but a little less penetration, under 12 inches a few times. Next was Triton, but quantifying this load was hard. Do I give the penetration of the deepest piece or take a weighted average of all the pieces? I went for both, largest pieces were about 13 inches deep, but only 20-50% weight. The weighted average gives about 10 inches. The Cor-Bon was similar, but weight retention was even less.

Consistency also has to go to Pro-Load followed by Federal and Gray Area neck and neck. Cor-Bon again is last. The stretch cavities were not consistent and the bullet paths were varied with the Cor-Bon. As far as barrier defeat, I was a bit surprised. The slower Federal kept the others at bay through most of the tests. While Pro-Load and Gray area were good at defeating barriers, the Federal defeated them and then performed better in media. Cor-Bon was terrible at defeating bone, glass, and wood but did well with drywall.

Defeat of 4 layers of denim and then media goes to Federal with about 11 inches consistently, but just by a shred (no pun intended) over Pro-Load (ave of 15") and Gray Area (ave. of 16"). Triton did okay with 10 to 19" but inconsistent and Cor-Bon was poor with only 5 inches of penetration on a few slugs and a few over 15". In short, Federal, Pro-Load and Gray Area did very well in the media tests. Even well considering that they were light bullet weights. I could not find enough differentiation between Gray Area and Pro-Load to give one 1st place over the other.

Cor-Bon: 5th

Federal: 3rd

Gray Area: 1st

Pro-Load: 1st

Triton: 4th

TEST #10 -- Function & Reliability

As the test involved the firing approximately 120 rounds of each type of ammunition, function and reliability was evaluated throughout the tests. All of the rounds, in addition to being fired for other tests, were fired rapid fire from a fully charged G27. They were also fired with hi-caps for the first few rounds of a full magazine and the last few rounds of a full magazine. Any malfunction attributed to the cartridge is noted and this test is judged as Pass/Fail. A fail gets 5th place points in the final standings and a pass gets first place points. No function failures or stoppages at all means the cartridge passes.

Cor-Bon: FAIL

Federal: PASS

Gray Area: PASS

Pro-Load: PASS

Triton: PASS

The Cor-Bon ammunition failed to lock the slide back about 70% of the time after firing the last round, from several magazines. None of the other rounds had this problem. When I switched to the Wolff guide rod and 20# spring, the problem was cured. Granted, the tenth round from a G27 is unlikely to be needed, but I want a defense gun to function as intended 100% of the time. This failure was new to me and my guess is that there is some dynamic related to the high slide velocity created by the Cor-Bon round. But, it appears to be cureable.


This has been a very enlightening process. Besides enjoying firing off around 700 rounds of premium ammunition, it has helped me to further define what is important in a self defense loading. Below I offer a final ranking of the five loads tested. But feel free to go back and look at the individual tests and decide if one test sways you strongly towards or away from a particular brand or load. Also, consistency, through-out the tests, was considered to be important. As such, the first place load is the load which I believe is the most worthy to trust with my life in a defensive loading. Also, the first place load was consistent throughout with no major drawbacks. In the final ranking, each individual test is worth 10 points. As there are ten tests, the total possible is 100. Each first place gets 10 points, second 8 points, third 6 points, fourth 4 points, and fifth 2 points.

Cor-Bon: 5th SCORE: 38%

Federal: 2nd SCORE: 80%

Gray Area: 3rd SCORE: 70%

Pro-Load: 1st SCORE: 90%

Triton: 4th SCORE: 56%

I plan to make a complete report of the full testing available in some format when it is finished. It may be a print version or an electronic version. If you have a strong opinion one way or the other, let me know.

Links to the Ammunition Companies

Cor-Bon Federal Gray Area Pro-Load Triton

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