Diamond Arms .410 single-shot - needs trigger

[12gaugeupgrade]

3-digit serial on this one; it belonged to my Great-Grandfather.

I understand that this was a trademark of Shapleigh Hardware in St. Louis, but there were several manufacturers. I know it's not a Belgian import -- no crown markings (and it's an old .410!). My father refurbished the stock and drilled the bore, blued the barrel.... in 1972. He also, sadly, lost the trigger and the firing pin in the same night-school gunsmithing class.

This is my latest project, and this is the oldest gun I now own; any help in identifying where I can find a trigger, hammer spring and firing pin for this old hardware-store break-open stagecoach gun would be appreciated. I'm aware that this probably hasn't much monetary value as a collector's item, but the sentimental value is something that cannot be priced.

Thanks, guys!

- 12 Gauge Upgrade
Bay Area, Occupied California

[freonr22]

numrich (www.e-gunparts.com) there were maybe 4 mfgs /names or so,

[freonr22]

here

http://www.gunpartscorp.com/catalog/Products.aspx?catid=12948

[12gaugeupgrade]

Doesn't it matter which manufacturer's version I have? Or are they all standardized even at that point? Will I need to ream the chamber to a larger size to fire modern .410 shells?

The barrel stamps read "HIGH PRESSURE SINGLE-PIECE BARREL" and ".410 BORE 12 M-M"

[freonr22]

tat part I dont know. I have a 16ga same as you, and shot it a few times. Fires fine. You would need to get current chamber dimensions, maybe from ammoguide.com? & use a caliper to confirm? do not have knowledge that .410 shell has more than one variation?

[12gaugeupgrade]

Do you have a schematic of any kind? I know I am missing the firing pin and the trigger, but I have the hammer in place -- which spring do I need is the question.

Some very old .410's (pre-WWI) as I understand it, are chambered for 2" or 2.5", and modern .410 sizes will not fit. Easiest way for me to determine this, I suppose is to get some .410 shells. All my other shotguns are 12-gauge.

Thanks so much for your help!

[SoCal Bob]

You may want to post your question in the Gunsmithing forum. I have an old, 20 gauge, Iver Johnson, Champion, single shot shotgun that will shoot modern loads because of when this version was made. Older versions of the same shotgun were designed for black powder and cannot take the pressures of the current loads.

Good luck.

[12gaugeupgrade]

Yes, this is going to be quite a project either way, SoCal Bob. Thank you!

From what I have read so far, the "high-pressure barrel" stamp means it was made for post-black powder loads, but that .410 wasn't really a US standard until around 1910 or so.

[freonr22]

I believe the Champion is the same socalbob!

http://www.gunpartscorp.com/catalog/Products.aspx?catid=5407

[12gaugeupgrade]

Thanks, Freonr22!

I don't see a firing pin for sale on Numrich - is it the floating head there in #801? Is there a Legend to go with it?

Again, your help is greatly appreciated. Merry Christmas!

[freonr22]

They Have a pdf for $1.50 or you can call them. Also try jack first company

[12gaugeupgrade]

I will call Jack First in the morning! Thanks for the ideas.

Is it just me, or is Numrich doing business on a website from 1998?

[freonr22]

sorry, last post was from a phone, Jack first has zero website, other than the contact number. called 2-3x usually a woman answers, is knowledgeable, get answer in 30 seconds or less

[Mike A]

The .410/12mm marking is one of the earlier designations for the 2 1/2" .410 ctg, which is still made. I wouldn't bother to rechamber the gun for 3" shells; you don't gain much--this isn't a goose buster. The short shells will kill quail and rabbits just as well as the 3" (some say better because they pattern better in many guns, especially full choke guns as this almost certainly is if it hasn't been rechoked). And the self-defense loads, should you be so inclined, are almost all 2 1/2" anyway.

You say your father "drilled the bore" in his gunsmithing course. What's that mean? Did HE perhaps rechamber to 3"? Try chambering a 3" in it (NOT shooting it). If it fits easily, it probably has been rechambered. But I'd still use the shorter shells it was made for.

This gun, as you probably know, has no collector's value now. But it obviously has family/sentimental value, and would, if in good, tight shape, be a very fun small game gun. I'm glad you're restoring it!

[12gaugeupgrade]

Mike A: Thank you so much for the information!

My father said that the bore had been badly pitted and corroded, and now it's quite shiny and new-looking inside. I'll pick up some .410 shells and try them on for size, but if I can still find the original ammo for it, my goal is to return it as close to original as possible.

Thanks again! I'm going to call Jack First about a firing pin now.