Jeff' Omega Breech Plug

[ronlaughlin]

Finally finished enough chores -- was able to put the breech plug to work. Don't recall a morning being this cold this time of year. Temperature was -9° when the shooting began. Shot as quickly as one could load, and aim without hurrying. Rifle was 45 caliber Omega with 2 - 7 scope. Load was 95g Blacklhorn, vegetable fiber wad, 275g star tip mz, 209A primer. Shot 12 times at top bull. Range was 201 yard.

Primers came out easily using trigger finger, and thumb. Primers were clean; no blow by. Ignition was stellar. Breech plug worked good. Air warmed quickly to 12° as shooting went on.

 

[goco4game]

Finally finished enough chores -- was able to put the breech plug to work. Don't recall a morning being this cold this time of year. Temperature was -9° when the shooting began. Shot as quickly as one could load, and aim without hurrying. Rifle was 45 caliber Omega with 2 - 7 scope. Load was 95g Blacklhorn, vegetable fiber wad, 275g star tip mz, 209A primer. Shot 12 times at top bull. Range was 201 yard.

Primers came out easily using trigger finger, and thumb. Primers were clean; no blow by. Ignition was stellar. Breech plug worked good. Air warmed quickly to 12° as shooting went on.

Love those clean breech plugs!
What is the actual group size, and are you happy with it?

 

[ronlaughlin]

Looks to be about 6". If the low flier is tossed, it looks to be a little over 4". No, am not happy with size of group.

 

[ronlaughlin]

Here is some numbers comparing Jeff' plug with TC plug.


Flame channel:

Jeff' = 5/32" diameter x 0.63" long
TC' = 1/8" diameter x 0.54" long


Head space:

Jeff' head space is 0.007" less than TC' head space.


Primer socket depth:

Jeff' = 0.207"
TC' = 0.162"


Flash hole:

Jeff '= 0.035"
TC' = 0.029"






This morning the intent was to do some shooting using Jeff' plug at 200 yard, but there were two tents, and a car near where the target would go. The site was aborted, and another site used. This new site has terrain such one can set up furthest at 185 yard, then again around 309 yard. A breeze began before shooting started; took time to get set.

Today the shooting was done at 185 yard. Load was 95 grain Blackhorn, vegetable fiber wad, Fury 285g Star Tip, Winchester W209 primer. Six shots at the top target from cold fouled barrel.

 

[01Foreman400]

Did you have a lot of blow by with the original breech plug? I’ve had my Omega for 12 years and I’ve never noticed any on mine.

 

[ronlaughlin]

TC breech plugs work fine. However, steps are taken to ensure no blow by when using the Omega rifles. Only W209 primers are used. Each primer is measured, and the primers shorter than 0.302" are culled, and labeled 'short'. Primers 0.302", and longer are shot in standard TC plug. Using these 0.302" or longer primers results in zero blow by..

The short primers are used in a breech plug that has been modified to use an o-ring. The o-ring makes the shorter primers work. When using the plugs with the o-ring, one can also use Federal 209A, and Remington STS primers in the Omega, without blow by.

Mostly curiosity had me purchase Jeff' plug, not so much need.

Jeff' plug does have at least a couple advantage over the TC plug.

TC plug have shallow primer socket; don't give much support to the sides of the primer. What happens then when it is warm, or when using a hot load, is the primers leak right through. A deeper socket helps stop this leaky primer problem.

Another advantage of Jeff' plug is the tungsten carbide bushing through which the flash hole goes. This flash hole doesn't erode nearly as fast as the flash hole in the TC plug. Right now the flash hole in this plug measures 0.034", which is 0.001" smaller than 0.035" when new -- wearing quite slow one might say. The flash hole of a TC plug would be 0.001" or 0.002" larger by now.