What size vent liner?

[jtpotter]

I have a 7/8 straight barrel in .45 caliber.
I bought a 5/16-32 White Lightning vent liner.
After thinking more about it and physically having the liner in my hand, I think I should go with the 1/4 inch liner. The 5/16 liner looks big.
I would think the bigger liner would be an advantage as far as ignition, the inside taper, I assume, is bigger.
What are your opinions?
Thanks
JT

 

[Vaino]

Used to use the 5/16 White Lightning, but now use the 1/4"....don't think there would be any difference in ignition. There's a possibility that if 2f was used w/ the 1/4", it might not fill the parabolic cone...but I doubt it. the 1/4" also size allows a little more leeway asre location.....Fred

 

[Zonie]

The flat widths on a 7/8" octagon calculate to be .362 wide.

A 5/16" thread is .3125 in diameter (although the female threaded hole will be a few thousandths of an inch larger than that).

If the vent liner can be exactly centered with the side flat, it should work without breaking thru into the next barrel flat.

That said, using the 1/4-32 threaded liner will allow it to be positioned so it is in the best position relative to the top of the locks pan.

There is also a little less chance that the threads for the liner will hit the face of the breech plug, assuming the barrel hasn't been positioned correctly.

 

[jtpotter]

Thanks for the replies. I went with the 5/16, cause I had it. It worked fine, centered between flats. It did run into barrel/breech threads just like Zonie stated. I shortened the liner so it wouldn't interfere with the threads.
Thanks again
JT

 

[Vaino]

If the liner infringed on the plug face, a cone shaped funnel needs to be filed into the plug face to achieve full exposure of the parabolic cone to the powder. Also, when a patch is pushed home, the debris could further restrict exposure to the powder.....Fred