Niple diameter

[Paulussie0]

Hi there !!

I am the "happy"owner of a replica underhammer.
Now I have got a question: does any one of you know what the max. diameter is of the flashhole in the nipple I have being told that the max diameter should be 0.80 mm.
Why this question? my gun is shooting superbly whit 0.8 bud there is a risk of damaging my lock.
If I put in a new nipple I Cannot get my gun to shoot as good as it did.
Any sugestions ??

 

[RedFeather]

What's the risk from, blowback? How heavy a load are you using?

Never much thought about what's ballpark for nipple inside diameter.

 

[silverfox]

What caliber is your underhammer is the first question and then what charge are you using. If it is blowback on the hammer you will almost have to go to a smaller dia nipple or reduce your powder charge. .080 seems a little large for a underhammer as it is directly into the chamber. Flintlocks .080 would be larger than most would use, most use between .060 and .075 and they don't have the power of a cap firing into the charge.
I had the same problem when I first got my underhammer, hammer blowback and them found I was using a hot charge for the caliber. Reduced the charge and solved the problem.
Fox :hatsoff:

 

[rice1817]

Bruce at[url] Underhammers.com[/url] turned me on to a guy name of Ron Bloomquist at BLOOMQUIST PERCUSSION WORKS, LTD. I ordered some replacement nipples from him specifically for my 50 underhammer. He is a most knowledgeable guy, and from him I learned that nipples need to be changes out a lot more often than you would think. Especially with heavy charges. He has a nice website. Check him out and he may be able to provide you with the information you seek.

 

[Paulussie0]

My caliber is .40 de charge is 60 grain ch2
the cap is rws (red label)
With a smaller diameter the accuratesse is compleetly gone

 

[walruskid1]

you may have to lower the powder charge since not as much pressure is leaving via the nipple. try a few grains less powder. a larger nipple hole is not a good thing on an underhammer. powder burns on your arm hurt!