Investarms Gemmer-Hawken Flint Kit

[rfd]

In essence this is a GPR flintlock in .50 caliber, 32" barrel, 1:60" twist for patched balls. I sold off the supplied coil spring lock in favor of the better L&R RPL05 flint lock an did the same with the stock DST for an L&R T5 DST. All this required extensive changes to the lock and DST inlets. The T5 DST need to have its rear end bobbed and drilled for the hold-down wood screw, and the front end stepped down 1/16" to accommodate the trigger guard's front end foot. As with most of these offshore "screwdriver" kits, there was some other minor mods required to get it the bbl and furniture to fit together, no big deal. The real nut was the lock and trigger work, but this ain't my first rodeo with kit guns

The gun as commercially completed and in kit form ...



The kit partially assembled with the L&R lock and the stock Investarms DST ...


The replacement L&R DST T5 for comparison to the stock DST, before the T5 gets modded ...



DST installed and tuned for very light trigger pull, ready for the laborious stock work ...

 

[eekjellander]

In essence this is a GPR flintlock in .50 caliber, 32" barrel, 1:60" twist for patched balls. I sold off the supplied coil spring lock in favor of the better L&R RPL05 flint lock an did the same with the stock DST for an L&R T5 DST. All this required extensive changes to the lock and DST inlets. The T5 DST need to have its rear end bobbed and drilled for the hold-down wood screw, and the front end stepped down 1/16" to accommodate the trigger guard's front end foot. As with most of these offshore "screwdriver" kits, there was some other minor mods required to get it the bbl and furniture to fit together, no big deal. The real nut was the lock and trigger work, but this ain't my first rodeo with kit guns

The gun as commercially completed and in kit form ...
View attachment 17451


The kit partially assembled with the L&R lock and the stock Investarms DST ...
View attachment 17452

The replacement L&R DST T5 getting ready to go in ...
View attachment 17453
View attachment 17454

DST installed and tuned for very light trigger pull, ready for the laborious stock work ...
View attachment 17455

Another fine example of your skill /Ed

 

[rfd]

Wood staining done. I used my favorite brand, Laurel Mountain Forge, one wipe of walnut, another over that with nut brown, and a final wipe of walnut, overnight drying for each coat. I'll pull off the breach plug, butt and toe plates, and begin wiping on Tru-Oil. I also made new ramrods using TOTW hickory 3/8" rods, stained with LMF Colonial Maple and then Tru-Oiled - I added epoxied and pinned brass ferrules (try and find the pins - nope, ya can't!). I leave the ramming ends of the rods plain but I slightly concave them and wick in water thin CYA to harden. In fact, before clear coating the stock, I'll wick in CYA to the lock mortise, breach plug mortise, and the entire bbl channel - this super seals the wood against BP mitigation. I had some American walnut left over from a lap steel fretboard build that I turned into a ball board - love me them speed loader ball boards!

 

[eekjellander]

That is going to make you a happy shooter for sure but if you ever get bored making ragged holes with it save me a spot at the head of the line of buyers/Ed

 

[rfd]

While the progression of clear coats go on the stock, with a coat in the early morning and one in the late evening, time between is spent on the barrel.

After wrapping the ignition end of the barrel with tape to protect, I use special octagon clamping cauls to vise the barrel tight. A witness mark is scratched across the breech plug and barrel, to be used to realign the plug when it gets put back on. A special wrench "nut" is slipped over the breech plug and a large Reed Corp wrench does the unscrewing deed. Investarms plugs come off fairly easy with the right tools.





There's always a lot of residue left after the manufacturer proofs the barrel ...





Which gets cleaned out with the help of Ballistol for both the plug and barrel ...



The touch hole line is screwed in and checked inside the patent breech flue - a bit of the end protrudes, it's removed and about 1/16" is filed off the end and is reinserted using Nikal anti-seize lube. The breech plug is screwed back onto the barrel after getting lubed with Nikal. All ready for firing once the gun is assembled.

 

[rfd]

All new and way too shiny for a hunting gun, but it'll be easy to rub it down with 0000 steel wool and then buff with beeewax for a hunter matte finish, once the the finish fully cures in a few days. Other than that, got the lock timing down smooth and fast, very light trigger pull after the set trigger is pulled, so she's ready to load 'n' fire.

 

[eekjellander]

Shiny but could be dull , the finish not your gun cause when your done it is all that it can be
(like that in the army sayin) a top notch job !/Ed

 

[rfd]

The "bent ramrod" is a 5/16" reclaimed from a .40 I once built, and used only for swabbing the patent breech flue - it's warp is of no consequence in that regard.

This gun won't be used for hunting by me, but none-the-less I don't like shiny gun stocks, so it'll get buffed out over the coming weekend. The bbl will be left as is, as I prefer. If it was for hunting, I'd vinegar patina it dull from the get-go rather than allow time to do its own relicing thing. The bbl has been "Lee Shaver-ized" with oiled patches and 0000 steel wool, and I haven't felt any tight or loose spots so far.

I am most pleased with what is more important that looks, the action and trigger. After setting the DST, the fire pull reads between 5 and 6 ounces on my Easton digital scale.

Range trip may not happen 'til next year, depending on the weather, of which I don't take kindly to much under 50F these dayze of my life.

Then again, it's patent breech gun, and I hate them damn things, maybe I'll just get rid of it.

 

[rfd]

5 to 6 ounce trigger pull ... sweet DST trigger assembly, and the lock time is Fast.

 

[rfd]

Some folks have asked me why I swapped out the lock and trigger assembly.

The concept of "better" and "best" can be somewhat subjective, at the least. For me, the quality, durability, adjustability, and performance of both the L&R RPL05 lock and the T5 DST is "better" than those stock Investarms components. Are there issues or known problems with the Investarms lock and DST? IMHO, no - both will work well, but IMHO not as well as those L&R components.

Be advised that these L&R components are no where near "drop in". A fair amount of wood will be required to hog out in order to get the lock to properly fit.

Before ...

After ...

The T5 DST will require its butt end to get bobbed by about 3/4" and a 1/8" hole drilled into it for the hold-down wood screw. Its front end will need to get a good 1/16" to 3/32" shelf cut/ground into it in order to allow the trigger guard to fit at least reasonably properly - I could have made that shelf deeper but felt it wasn't all that necessary, didn't want to perhaps weaken that part of the DST, and having the front end of the trigger guard be proud of the stock wood wasn't a deal breaker (for me).

DST comparisons ...