GTA

All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Poorman Plinker on August 19, 2015, 12:05:39 PM

Title: 177 vs 22 barrels
Post by: Poorman Plinker on August 19, 2015, 12:05:39 PM

Here is a comparison of .177 and .22 when shot out of different length barrels with co2. This was first posted in the Crosman/Poorman Plinker facebook group.  Of the barrels previously tested there were only 3 of the same length in both .177 and .22. The results of comparing the two test’s data showed that the .22 caliber is more co2 efficient but there were still advantages to the .177. The three barrels tested were 24”, 18” and 10.25” and the test procedures on the 2240 platform have been previously described. (Sorry the graph did not copy and the numbers are jumbled)

            .177–24”   .22– 24”   .177-18”   .22– 18”   .177– 10”   .22– 10”
Hi              654 fps   569 fps   651 fps   553 fps   556 fps   482 fps
Lo              631 fps   523 fps   631 fps   525 fps   529 fps   467 fps
Av              644 fps   551fps   642 fps   544 fps   546 fps   474 fps
SD                    6              16           6               9           7              4
Fpe             6.82         9.64     6.77        9.40          4.90            7.14
Fpe/in          .28              .40   .38              .52   .48               .70
# in 15       10                 9   13               11   14               15

Comparing the different calibers in the 3 different barrel lengths it is apparent that the .22 barrels resulted in higher fpe than .177 barrels fired on the same platform. The averaged fpe increase of the 3 barrels in .22 over the three in .177 was 2.56 fpe with the 24” producing the highest difference (2.8 fpe). Also the fpe/in was higher in .22 for each barrel. The data shows the fpe related numbers favor .22 but the .177 had better results in other areas.


Avg. of 3 barrels             .177   .22
fpe                                    6.16   8.72
Fpe/in                              .38   .54
Increase from               15.2%       13.9%
 10” to 24”   
# of shots in 15 fps   12.33   11.67
SD                                    6.33   9.67

The average fpe of the .22 barrels is 2.56 greater than the .177 barrels.  However, from the averages of the two calibers you can see that the .177 showed a better increase in velocity from 10 to 24 inches and a higher number of shots within a 15 fps spread and the standard deviation of the shots fired were smaller than that of the .22. Except in cases where 2 fpe could make a substantial difference it appears that the .177 is a superior performer in velocity increase and tightness of velocity spread and helps explain its popularity with target shooters. 8)

Title: Re: 177 vs 22 barrels
Post by: Geoff on August 30, 2015, 11:23:09 AM

thank you for the numbers