So I finally got some shooting done! The results were certainly not what I was hoping for but I learned a few things anyway so not a waste.
Thomas Edison apparently said “I haven’t failed, I have found 10,000 ways that don’t work.” My response is ~ “Amateur!” I could teach Mr. Edison a thing or two about what doesn’t work! (at least with shotgun slugs)
Nonetheless, there were lessons learned and trends that held up.
I have tried a variety of plastic wads, fiber and card wad combinations and fillers. So far the best and most consistent results for me have been with a solid column of hard card wads with a plastic gas seal under them.
Not to say that good accuracy cannot be had using plastic wads. I have had some good results shooting 0.662” round balls in shotcups and many others get good results, but generally, I have had best results when using hard card wads especially with heavy slugs.
I have been leaning towards bore size slugs anyway just to eliminate that wad variable and I think the results of this outing have convinced me that bore size is the way I will go.
What got me going for this test was diehard and his Rocket Slugs.
I had made the 6 finned (or vaned) mould up a few months ago on the basis that the fins would give the wad column better support than a hollow base slug, it has a heavy solid nose and that the fins could be bore size but would swage to suit a choke. I made several attempts to get them to shoot and was unsuccessful (results posted) so was going to modify the mould to a ribbed hollow base. Then diehard posted photos of the Rocket Slugs. They were so similar to the slugs I made that I got interested again. He got some promising results and offered to send 5 Rocket Slugs to me for testing. How could I refuse.
So, diehard provided the 5 Rocket Slugs and I decided to try the finned slugs again, both bore size and also turned down to fit into a shotcup. I took 5 finned slugs and turned them down from 0.730” diameter to 0.680” diameter.
I also thought while I was at it that I would load up some more TC slugs and wadcutter slugs from a mould I made. While I haven’t gotten really good results, all the holes in the targets have been nice and round so they fly well. I have also had several wads blow so attributed poor accuracy to a bad launch.
I also decided to try a Brenneke or AQ inspired test. I have tried several methods of making homemade Brennekes and AQ’s with mediocre success and they were lots of work to make. I concluded that generally good but sometimes erratic accuracy was due to inconsistent wads or attachment. So this time I decided that using copper tubing parted off would give a repeatable “skirt” under a round ball. I punched 0.662” round balls, wound a short wood screw in then set the short piece of copper tube on the ball with screw up and filled with hot melt glue. Fairly quick and easy to make, and reasonable accuracy.
Loads as follows:
· All hulls Fiocchi 2 ¾”
· All primers Winchester 209
· All powder charges = 34 grs. of Blue Dot
· Wads and gas seals from Pacific Versalite wads
This load was based on a load I worked up and has proven safe under slugs of up to 600 grs. using 38 grs. of Blue Dot. However, it was slapping me stupid (okay, more stupid) and I found I was collapsing slug skirts and fins so reduced it to where recoil was tolerable and it didn’t seem to hurt slugs so much.
Also, of the plastic wads I have tried the Pacific Versalite have held up well in the past even when I used the gas seal over 38 grs. of Blue Dot pushing a 600 gr. full bore slug. I have blown several other gas seals but not these ~ until now!
Guns used:
o single shot break action cylinder bore for all but the Rocket Slugs
o Browning BPS with I/C choke slug barrel used for Rocket Slugs
o All shooting was at 50 yards
The reason I used the Browning for the Rocket Slugs is that it has shot well for me and diehard mentioned that best results with the Rocket Slugs were with some choke.
So, on to results:
0.662” Round ball/copper tube
· 0.662” round ball/copper tube with hot melt glue filler
· Weight = 570 grs.
· Group size = 3” wide x 8 ½” high including one flyer
· 2 slightly oval holes
· All gas seals blew and wads were in poor shape
Wadcutter Slug in Shotcup
· Weight = 550 grs.
· Filled with cornmeal
· Group size = 4 in 5 ½” wide x 16” high; 1 outside flyer
· All holes round
· All wads in good shape
TC Slug In Shotcup
· Weight = 525 grs.
· Filled with hot melt glue
· Group size = 5 ½” wide x 10” high; 1 flyer
· All holes round
· The 4 wads recovered were in good shape
Full Bore Finned Slugs
· Weight = 580 grs.
· Oven heat treated
· Loaded over cushion leg (none recovered)
· Group size = 2 in 2 1/2” wide x 1 ½” high; 3 misses
· Oval holes
· No cushion legs recovered
Finned Slug in Shotcup
· Weight = 500 grs.
· Oven heat treated
· Loaded into Pacific Versalite wad
· Group size = 1 on the paper
· Round hole
· The 4 wads recovered were in terrible shape
Rocket Slugs
· Weight = 410 grs.
· Loaded into Pacific Versalite wad
· Group size = 3 in 6 ¼” wide x 1 ½” high; total group size 13” wide x 12” high
· 2 hit sideways
· wads were in pretty good shape with one slightly blown gas seal
Basically all accuracy results were mediocre to downright horrible. Some groups I am sure could have been better if the shooter was more consistent and it hadn’t been so windy. However, that doesn’t explain missing a 24” x 36” piece of paper at 50 yards!
None of the loads showed any sign of excess pressure but some did leave quite a bit of unburned powder in the bore, possibly making groups sizes larger.
I was rather surprised at the carnage done to the wads. This was not a really heavy load and I have no good explanation for the severe wad failures. The finned slugs likely allowed enough distortion that there was gas leakage causing burning and failure but why the wads used for the solid base copper tube slugs failed I do not know.
I have used heavier powder charges under heavier slugs with the same gas seal but under hard card wads without any seal failures.
The 2 recovered Rocket Slugs showed substantial fin collapse but most of the wads look pretty good. I think this is due to the light slug and relatively low pressure.
The Rocket Slugs appeared to be approximately as hard as ACWW. The fins are slightly tapered and run from about 0.070” at the edge to almost 1/8” where they join. There is not as much cross sectional area as my 6 finned slugs so I am not sure how the manufacturer planned to avoid fin collapse. I used relatively slow Blue Dot and a moderate load so I am pretty sure a faster powder would cause as much or more fin distortion.
I am still intrigued by the finned slug design so haven’t completely given up yet. I also took lots of photos and dimensions of the Rocket Slugs and have modeled a mould cavity in 3D. I think the mould would be quite easy to make so if anyone is interested I can provide dimensions and the 3D information and method to a mould maker. The Rocket Slugs are made in a split mould.
I will be making a new core for my 6 finned mould to try 3/32” fins instead of the 1/8” fins it now has then I will try again. This will lighten the fins a bit and make them a little more aerodynamic but it will also make them more fragile.
I will also be modifying the core of my current 6 finned mould to produce a ribbed full bore hollow base. So far my best results with hollow base have been with the Rapine 730550 which gave 2” groups at 50 yards from this same gun. I will be trying to repeat that as I have a few more Rapine slugs to load.
So, what did I learn from all this and other tests? Well:
· I think full bore slugs and balls are easiest to get consistency with.
· For ease and simplicity of loading I still like full bore round ball and have gotten decent accuracy to 50 yards with it from smoothbore and good accuracy with rifled bore.
· Gas seals like a really solid flat base above them.
· Failed wads and/or gas seals really cause havoc with accuracy. The exception here seems to be the 0.662” RB/copper tube slug which gave reasonable accuracy even though all wads looked like they went through a blender.
· Next time out I will be shooting full bore round ball and filled hollow base or Brenneke/AQ style with good hard card wads and good support for the gas seal.
· Remember to take a really thick shoulder pad with me when slug shooting.
Last but not least, I would like to thank diehard for sending me the Rocket Slugs for testing. These are a little slice of history and I appreciated the opportunity to handle them, measure them and shoot them.
That’s all I got for now.
Longbow
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