Range Test of My GRF 20ga. SB with a .572" RB

[Maven]

I've been experimenting with my Green River Forge 20ga. NW Trade Gun with no rear sight (.618" - .619" bore as best as I can determine). Generally, I use a patched RB between .597" and .604" (Lyman mould, which casts .600" - .604"). I even had Tanner Ball Moulds make me one to fit the bore, i.e., .618" Although the Tanner RB casts well, accuracy wasn't as good as the smaller RB's. Today, after heeding Waksupi's advice about a looser fitting (thumb started) RB, I took the plunge and tried a .572" RB (actual diameter, pure lead) that I cast from a newly acquired Lyman mould.

About the new Lyman mould. I got it from eBay at a good price as it was almost certainly new. Although it was marked .575", it casts a bit smaller @ .572", but it casts extremely well and a smaller mould was what I was looking for anyway. Since I knew what patch thickness - RB diameter worked with the ~.600" diameter RB's, it didn't take long to come up with the magic number( patch ball diameter) even if it meant using two patches. After searching through my fabrics, I settled on a .020 + .014" patch with the .572" RB, with a brief side excursion into tow wads fore and after for 3 shots.

What you see below are two targets, The first is with patched ~.600" RB's (Tanner, Lee, and Lyman. The bore size RB results aren't shown). The second target is from earlier today and shows tow wad results (80gr. GOEX FFg and the largest group), 5 shots using the .020" + .014" patch combination (70gr. GOEX FFg and second best group), and lastly a 3 shot group with 2 pillow ticking .014" patches.(70gr. GOEX FFg) and the smallest group. Btw, all shooting was done with front and rear bags at 25 yd. Patch lube was 1 Ballistol : 6 water and no swabbing of the bore.

Waksupi's right: a smaller patched RB may be something you should try.

 

[lbothell]

Nice write up! I too have been experimenting with going smaller in the 70 caliber trade gun, but I’m trying to get down to 54 caliber round ball. Experimenting with plastic shotgun wad and a patch. Haven’t shot it yet till I get a couple more ideas so I can test em all out. Some people don’t like this stuff but I think it’s fun, thanks for sharing and hope you continue with it. It’s always fun to make a gun more versatile

 

[Maven]

Nice write up! I too have been experimenting with going smaller in the 70 caliber trade gun, but I’m trying to get down to 54 caliber round ball. Experimenting with plastic shotgun wad and a patch. Haven’t shot it yet till I get a couple more ideas so I can test em all out. Some people don’t like this stuff but I think it’s fun, thanks for sharing and hope you continue with it. It’s always fun to make a gun more versatile

I agree, they may be smoothies with no rear sight, not bench guns, but that doesn't mean we can't monkey with them in order to improve accuracy. Indeed, that's part of the challenge/fun!

 

[Taevers]

I agree, they may be smoothies with no rear sight, not bench guns, but that doesn't mean we can't monkey with them in order to improve accuracy. Indeed, that's part of the challenge/fun!

I’m right behind you on this lil rodeo. I’m going to the range tomorrow with my new Fowler and will take some pictures of my targets. I’m glad you shared your experience and targets. I have some .024 denim dipped in melted goat tallow. I’ve only .575 from a Lee mold to play with but intend to try the larger ones next.

 

[WALT53]

I agree, they may be smoothies with no rear sight, not bench guns, but that doesn't mean we can't monkey with them in order to improve accuracy. Indeed, that's part of the challenge/fun!

Well you definitely got the challenge part right my thoughts are that smoothbores can fussier than a princess.

 

[Billy-by-gosh]

Well you definitely got the challenge part right my thoughts are that smoothbores can fussier than a princess.

Ah yes, but when you hit upon that magical load formula, how sweet it is!