Finally I got to finish the project I wanted to do way back in June. My shoulder feels about as good as ever, and I was able to handle the 1 1/2 oz baby magnums with no issue. I think I have some interesting results to report. Some are real eye openers. Some leave more questions than answers. Also the RP12 wads were donated by a member here. It has been so long I can't remember who it was. So thank you if it was you.
This test took the entire day. I started in the morning, got shooting by about 11 and didn't finish until about 6. I've been counting holes in paper for the past few hours. This picture is my pickup after I finished shooting. That's quite the stack of pattern paper. I tried to do 5-shot averages, but a number of them had to be 3-shots due to issues with the chronograph or pressure gun.
First just a disclaimer. This is not to be considered load data. Only two of the loads listed come from a published reloading manual. The rest are wild cats. Use at your own risk. You will also note the pressure appear high in one, and low in another. You have to keep in mind I did not calibrate my test guns The 16 gauge I just put a new strain gauge on it yesterday. The 12 gauge should be fairly close, but I did not run any of my calibration loads to check it. Weather was quite warm, about 85 degrees and I was out in the sun. I had no way to shade the ammo. This is not a laboratory, I'm testing in the outdoors. Instead just focus mostly on the A to B testing, which is what this is all about.
I'll start by listing the loads. I'll be referring to them by their letter farther in the post. This is how I organized all the patterning too. All loads had both the shot and powder weighed. I used Lawrence #5 magnum lead for every load.
12 gauge
A:
2 3/4" Federal Paper
Federal 209A
34gr Bluedot
RP12
1 1/2 oz lead
fold crimp
B:
2 3/4" Federal Paper
Federal 209A
34gr Bluedot
(2) 1/8" 12ga nitro cards + (1) 1/4" 12ga felt wad
1 1/2 oz lead
fold crimp
C:
2 3/4" Federal Top Gun gen 3 with plastic basewad
Federal 209A
18.5 gr 700X
Downrange clone 12S3
1 1/8 oz lead
fold crimp
D:
2 3/4" Federal Top Gun gen 3 with plastic basewad
Federal 209A
18.5gr 700X
(1) 1/8" 12ga nitro card + (2) 1/2" 12ga lubed fiber wads + (1) 12 ga overshot card (under the shot)
16 gauge
E:
2 3/4" Fiocchi
Fio 616
15.5 gr American Select
Claybuster CB0078
1oz lead shot
20ga overshot card
fold crimp
F:
2 3/4" Fiocchi
Fio 616
15.5 gr American Select
(2) 1/8" 16ga nitro cards + (2) 1/4" 12ga felt wads
1oz lead shot
20ga overshot card
fold crimp
G:
2 3/4" Fiocchi
Fio 616
15.5 gr American Select
Claybuster CB0078
1oz lead shot
fold crimp (no overshot)
H:
2 3/4" Fiocchi
Fio 616
15.5 gr American Select
(2) 1/8" 16ga nitro cards + (2) 1/4" 12ga felt wads
1oz lead shot
20ga overshot card
roll crimp
A quick note on those loads. That's not a typo on the 16 gauge, I used 12 gauge felt wads, and yes those are CB0078 wads with 1 oz loads. In the 12 gauge fiber wad loads I used lubed wads and I lubed them myself with bear grease. I did not soak them, I only lightly rolled the sides of them in it. I was hoping to only lube the edges, but it soaked in, so they are very lightly lubed. I have no idea how much the lube effected the test, if at all. My thinking at the time was to create a "worst case" scenario with a ton of lubed cushion, and minimal sealing nitro card. You will see how that turns out later.
Here is the pressure testing data using my Pressure Trace II. For the 12 gauge I used a Mossberg 500 with a 28" barrel, the same I've been using for a few years. The 16 gauge is a Stevens 530A with 28" barrels which I've also used a long time, but the old strain gauge got damaged in the gun safe. I glued a new one on yesterday, and never calibrated it. I did run some published loads through it to check function, and they appeared normal pressure, but it could be off 1000-2000 psi. Note that loads A and C are published tested loads.
Pressure Data
12 gauge
A: 13,239 psi
B: 14,015 psi
C: 10,631 psi
D: 11,279 psi
16 gauge
E: 6,141 psi
F: 5,449 psi
G: N/A (saw no reason to test)
H: 5,124 psi
I tested velocity with 3 guns in 12 gauge, and 2 in 16 gauge. I had a lot of trouble with load B for some reason, I'm not sure I would trust it. I only got a couple good readings. I'll number the guns. The guns in 12 gauge were the same (1) Mossberg 500 with 28" barrel, a (2) Winchester 1897 with 30" barrel, and a (3) Benelli Nova with 28" barrel with an extended choke which brings it to 30" total. In 16 gauge I had the same (1) Stevens 530A with 28" barrels, and a (2) Remington 11-48 also with 28" barrels.
Velocity data
12 gauge
A1: 1286 fps
A2: 1326 fps
A3: 1266 fps
B1: N/A
B2: 1262 fps
B3: N/A
C1: 1216 fps
C2: 1238 fps
C3: 1218 fps
D1: 1175 fps
D2: 1204 fps
D3: 1184 fps
16 gauge
E1: 1110 fps
E2: N/A
F1: 1066 fps
F2: N/A
G1: N/A
G2: 1110 fps
H1: 1038 fps
H2: 1034 fps
Next up is the real meat of the testing, the pattern testing. Again I'll number the guns. For 16 gauge I used both the (1) Stevens 530A and the (2) Remington 11-48. In the Stevens I used the left barrel which has a modified choke. The Remington also has a modified choke barrel. In 12 gauge I intentionally chose two guns as opposite as I could. I chose the (1) Winchester 1897 because it has a 2 3/4" chamber, and it was built when natural/card wads were all there was. I have not measured the forcing cone length, but it does not appear to be any different than a modern shotgun. It has a full choke barrel. The (2) Benelli Nova I chose for the 3 1/2" chamber. It is also about as new as a shotgun gets although the forcing cone appears no different than the Winchester. I used a Carlsons extended full choke for all tests.
Pattern testing was done at 40 yards, measured with a tape. I then counted pellets inside of a 30" circle. I centered the circle on what appeared to be the center of the pattern. I shot mostly 5-shot averages, although some are 3-shot. The results I will list as averages. I added up the pellet counts, then divided by the number of patterns. 1 oz of my #5 Lawrence has 174 pellets. 1 1/8 oz is 196 pellets. 1 1/2 oz is 261 pellets. I'll list the average pellets inside a 30" circle first, followed by the calculated pattern percentage.
Pattern results
12 gauge
A1: 200 pellets 77%
A2: 203 pellets 78%
B1: 169 pellets 65%
B2: 117 pellets 45%
C1: 153 pellets 78%
C2: 142 pellets 73%
D1: 160 pellets 82%
D2: 148 pellets 76%
16 gauge
E1: 126 pellets 72%
E2: N/A
F1: 116 pellets 67%
F2: N/A
G1: N/A
G2: 126 pellets 73%
H1: 118 pellets 68%
H2: 126 pellets 73%
That's a lot to take in. Conclusions to follow...