Thanks Longbow, ended up putting a 3-12x scope. I need to measure the bore to see what im working with.
Thanks Longbow, ended up putting a 3-12x scope. I need to measure the bore to see what im working with.
Finally got around to modify the original mold to a semi-sphere design. The modification brought the combined weight of wad and slug up to 490 grains - a bit heavier than my original plan, but I can always make a new and shorter mold. As a bonus, the center of mass has shifted forward a little which should be a good thing.
Next step will be to load up a handful of subsonic loads to test at 100 yards and see if the slugs still tumbles after the fifty yards mark. If it doesn't, I'll try with a supersonic load to see if anything changes and if a slug-tumbling gremlin really lives in the transonic area.
Cap'n Morgan
Those look great. Interested for the results!
Great work, good test plan. The nose heavy feature will power it through destablization forces I believe.
"My main ambition in life is to be on the devil's most wanted list."
Leonard Ravenhill
Cap'n:
Those are looking a lot like the old AQ'S! Big difference is AQ's had a hole in them that the wad inserted into where you have the lead tit sticking out to go into the wad.
How does that leading edge of the wad hold up? I had thought it looked a little fragile and might flare out after being squished between bore and slug nose.
Those slugs do look good though. I'm with Kracken... I wish we were closer so I could pilfer your slug stock and do some field testing.
That design looks like a good one for zinc slugs too. I suspect that in not too many years lead will be on the endangered list for boolit material. A guy has to look ahead!
As always, terrific work and pics!
Longbow
Longbow.
I haven't got around to examine any of the slugs after impact but I plan to do so. We have a small shooting range a few miles from here where I sometimes run impact test. The range is situated in an old gravel pit which holds some extremely fine-grained sand which does very little damage to the slugs. A large snowdrift would be better, I know, but most winters we're low on snow - which is a darn shame as my favorite hunting objects are foxes in the wintertime.
It shall be interesting to see if the tumbling is somehow related to the transonic area and if the new design will improve things. Should it happen that the slug will behave at subsonic speeds but cannot cope with the transition I'll probably change the mold to as heavy a load as I can safely get away with. Might as well pack some punch...
Cap'n Morgan
Many years back when I tested some Dixie Tuskers I got mediocre to poor accuracy from them from my smoothbore (while HB they are designed for rifled guns). Holes were round in the paper at 60 yards so not showing signs of wobbling but I decided to try them to 100 yards to see if they still flew straight so lined up target frames at 60 yards, 60 yards, 75 yards and 100 yards with about 3' x 4' paper and set a target hig hon the 50 yards paper then shot. While groups were large all holes were perfectly round through all the papers.
The Tuskers I had were sized to 0.727" and hard cast (like cast iron! Hard!) and shot from a 0.733" bore so rattly. I figured they were nose heavy enough to be stable but were leaving the muzzle at slightly different angles each time. Regardless once in the air they seemed to fly well. I may have mentioned I like the Tusker design!
There I go rambling on again! Point being that you might try the same thing and line up 3 or 4 target frames with big paper then shoot and check holes at each range. If the slugs lose stability past 50 yards you'll know in very few shots.
We have very fine sand here too and lots of it! I was shooting into it last Sunday and recovered several slugs. I'll be writing that range day up shortly.
I've got faith in you Cap'n! You'll beat this instability thing.
Longbow
Did a test yesterday to see if the new slug profile would be stable at subsonic speed. I didn't use a chrono, but the estimated speed was about 1000 fps or less. The range was 90 yards and I just fired 3 rounds to check if the slugs still was flying nose-on at that range. Well, let me tell you; They didn't! All three shots hit the target sideways as per the picture.
The three shot marked with a triangle was the result of my previous test at 100 yards. At that time I was a little puzzled that all three imprints was sideways in the target, but thought it was just a coincident. This time around the three shots (marked with a circle) showed the exact same behavior. This can't be a coincident. I wonder if the slugs are not tumbling, but actually fluttering the "tail" from side to side like a car out of control on a slippery road. This could explain the sideways impact as the slug is only flying nose-on for a very short time between the jerks. Notice that the group is a respectable 6" - not bad at 90 yards, but the ballistic must be horrible.
I'm afraid this slug is too short and the center of mass should be further forward. There's still a couple of things I will try, but chances are this slug will not fly properly beyond 50-60 yards.
Cap'n Morgan
Perhaps the result would be better with a much faster load, say 1500 fps.
"My main ambition in life is to be on the devil's most wanted list."
Leonard Ravenhill
Maybe you should try the AQ approach and put a hole into your lead nose cone then put a tit on the wad to press into the hole. That would move the CG forward about as far as it can go. You can always lengthen the nose cone a bit to get to same weight as now. The AQ's I had were very nose heavy and basically balanced... just a nudge and they would stand on their noses.
Did you recover any slugs to examine the plastic tail wad? I still wonder if that thin front lip might be opening up a bit after being squeezed between bore and nose cone. That could make the slug unstable if it is opening up at all.
My solid "Brenneke/AQ" like slugs are flat bottomed then I put a #10 wood screw in a cast-in starter hole and cast the hot melt glue skirt onto the base. That holds amazingly well. Yours would be classier than that by far so should work well. I was actually trying to copy AQ's as best I could with what I have and they work well if the skirt is well cast.
As for the wobble you mention, I agree that is likely what's happening... a rapid/violent flipping from side to side. There's some slo mo video I've seen (likely Taofledermaus) with slugs showing that sort of tail oscillation.
Like I have said... I think there is black magic involved with getting good and consistent performance from smoothbore slugs!
Longbow
I think I'll try HT's suggestion and try raising the speed - probably make a new mold as well; 1500 fps with a 500 grains slug is not my cup of tea.
Longbows suggestion will be next in line. It will be a little more complicated than my first design, but it will be much better wrt the balance in the slug. It's back to the drawing board once more <sigh>
Cap'n Morgan
Not sure if you are familiar with the AQ's but I believe they are of European origin though BPI marketed them here like they were a BPI product.invention.
Here's a link with pics:
http://www.guns.com/2017/06/02/slugg...gun-slug-load/
The ones I tried shot very well from my Browning BPS slug barrel. If they hadn't been so expensive to buy I'd have bought a truckload of them. The only real downside is that they were soft lead. A wad slug version with hard cast would be great and is what I tried with my hot melt glue skirts with some success. With your injection moulded wads you would be able to reproduce these or similar maybe as a short fat conical weighing 500 to 600 grs.
What I liked was that they were so nose heavy they just rocked up on the nose with the slightest nudge.
I know you'll get this beat however you approach it Cap'n!
I am a bit familiar with that "back to the drawing board" thing...
Longbow
It always makes me wonder how Brenneke got it perfect so long ago. To me, just laser eye-balling that stem, it has quite a bit of meat to it. I think those are just too tail heavy. I like that you went with a cast stem slug, rather than a hollow base, but I think you will need a longer plastic tail. For a test, I've thought about trying to glue some felt wads on slugs. I've never tried it, but it might be just the trick here.
I think glue will fail or the wad will fail at the glue line. It's worth a try but those wads take a beating at 10,000 PSI! I tried screwing nitro card wads on as tail wads and they delaminated and were all scraggly when recovered. Some of the scraggly was due to impact but not all of it I am sure. Accuracy was poor.
The screw through the butt has worked well for Brenneke, Vitt Boos and some others for a long time.
In fact, next order I put in will include some felt wads from BPI to try something similar to the Brenneke with screwed on felt tail wads. It is something I have not tried but should have long ago. I went to the cast on glue wads which work but are a bit tedious to do. I think making up a punch to put a screw hole in the center of a felt wad would be pretty easy and fast to do. My slugs have a cast in screw starter hole so not problem there. If it works, great! If not I've got some felt wads for spacing/cushion.
It is amazing that there never seems to be an end to what can be tried at this game! I've slung hundreds of pounds of slugs downrange over the years and am still looking for the elusive 100 yard "nice" group. Done it with factory slug loads and factory made slugs handloaded but not home made slugs... yet! Consistency is the name of the game I think, that and solid wad column.
Give it a go and see what you get. It's all good stuff and fun trying things. We keep learning.
Longbow
I've been buying a lot more from Precision Reloading recently, and I've found their felt wads to be better. BPI 1/8" thick are OK, but their 1/4" versions look like two 1/8" stuck together. The PR ones are perfect by comparison. I also find the fiber wads from PR are less stiff, yet hold together much better than BPI. I think a dab of silicone with a 1/4" felt wad would stand a good chance. I've had card wads glue themselves to slugs accidentally with nothing but a tiny dot of bullet lube. It would at least show if a longer tail would help.
I may have to try Precision Reloading for those then. Not sure if they'll ship to Canada though. BPI used to but there is a Canadian BPI rep in Alberta who is good to deal with so no cross border problem there. It depends on the dealer and product whether they will ship to Canada. Makes it tough in rural areas where there are no large guns shops and reloading supplies.
I'd still think that the felt should be trapped between a couple of leather or tough plastic washers like Brenneke does. If the trailing edge of the felt gets ragged it will affect accuracy. I've long maintained that consistent dependable wad column and in the case of attached wad slugs, consistent attached wad are essential to consistent accuracy. It doesn't take much to cause inaccuracy.
The old Brenneke classic slugs looked to me like they were assembled then a punch run over the assembled slug to shear the wad to final size. However they did it the slugs were extremely consistent. Nowadays with injection moulded plastic tail wads can be virtually identical. It is tough for the basement tinkerer to match that.
Longbow
Well, I'm finally getting ready for round three with my latest slug design.
The previous design, while accurate and stable up to about fifty yards, it would hit the target sideways at longer ranges. I decided to go with Hogtamers suggestion of a faster load - preferable around 1500 fps to keep the slug supersonic for as long as possible.
To accomplish this the slug had to be lighter - alas, a new mold had to be made. The new slug is much lighter - combined weight of slug & wad is 375 grains or 24 grams - same weight as the 1500 fps target loads we use over here.
I hope the new profile and increased speed will create a true drag on the rear of the slug and keep it pointed nose forward.
The old subsonic design would start wobbling profusely after fifty to sixty yards - perhaps caused by the pressure wave building up in front of the slug.
Now it only remains to work up a chronographed load and test for accuracy and stability.
Cap'n Morgan
That's awesome...unforunately my 525 Lyman still is covered I in factory oil.
Those look good for sure...good luck!
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |