sabotloader

Breechplug

OK - first off remember I am not a good writer and what makesense in my head may not make sense verbally at all to anyone but me.

Yes, I have modified several plugs now. Lemoyne has done the same thing to some other plugs also.

I have modified Omega/Encore plugs - Knight DISC plugs and about to modify a Knight Vision plug.

Let's make sure you and I are talking about the same thing... The 'flash channel' is the area directly below the primer that lead to the smal 'flash hole' in the nose of the breech plug.

Spitpatch is the person that started me on my adventure. He mentioned one day about how clean the new Vision plug was and indicated that Knight had opened the 'flash channel' from 1/8" to 5/32nds. Then I satarted thinking about the Triumph breech plug - why is it so darn clean... Answer - both of those plugs now have the ability to hold more blow back volumn in the flash channel - the Triumph because it is much longer and the new Vison plug because it will hold more volume - the abilty of the 'flash channel' to hole more volumn allows the bullet to exit the barrel before the blow back can be pushed out around the primer... the act of the bullet and pressure leaving the bore then actually sucks the flas channel clear of gases. Somebody else could explain this a lot better.

So I have opened the flash channel larger + I have installed a Lehigh vent liner. The vent liner in itself helps deflect blow back away from the 'flash hole' just by design.

The size of the 'flash hole' is a prime factor in ingnition of the powder but it also can and will allow more blow back back through the primer if it is to large. I think and believe a 'flash hole' diameter of .032 is about prime. Some people have opened this to .036 but that is to large for me. Lehigh Dave did spent a lot of time developing the correct size 'flash hole' and settled on the .032.

Here is a picture collection of what I am doing. Lemoyne is doing about the same thing...



Here is completed Knight DISC plug...



And this is a picture looking through a modified Omega plug... The channel has been opened to 5/32nds




There certainly could be a sealed breech - but think about a sidehammer - how many times have you really wanted to clean the BP.... + Breech Plugs do wear out especially inline plugs that are shot very hot and very hardso they need to be replaced....

Any of this makes any sense.... to anybody

Breechplug

Yes and Thank's Mike, I was wondering where you went...LOL!
(BP)

tjj

I've been following some of the posts on various sites about modifications. As previously stated, the smokeless guys are doing a lot of experimenting(as are bp shooters). It seems to me that a larger flame channel and a vent liner are about all that would be needed to prolong the BP life indeffinately. Blowback seems to be virtually non-existant on a lot of the newer models(breech area). It seems that convenience is King in todays market.

sabotloader

Breechplug

i am a dang slow typer - dang slow an i kant spell woth a darn

tjj

I must be really slow typing, SL put the whole format out there before I could describe what I was trying to say. Thanks Mike.

fusion

I have a Savage 10ML-11, BP has the replaceable vent liner. Needs to be replaced about every 100 shots. No blow back what so ever. Just picked up some after market Vent liners that are suppose to be good for 200-300 shots.

Screwbolts

Hi Ron and all,

The design of Breech Plugs,

IMHO, BH209 is not the problem or reason for carbon in your Breech Plug, does your barrel build up with carbon?? Mine doesn't, IMHO the 209 primer is the problem!! The carbon is from the primer not the powder.

What was the 209 designed to do? The Standard Non 777 Modifed 209 primer was not and is not Designed to light powder in Muzzle Loaders, Rifles or ML Shotguns! It was designed to light Powder in a shot shell. In a Modern Shotgun all the garbage from the primer was blown out the barrel, not a big problem. How many of you know that there used to be more than 3 different physical sizes in Shot gun primers, How many of you still have Rem. 157 and 197 primers in your collections. Also, how many of you know that there is no standard for the length of a 209 primer. Hard to build a Breech plug that will perfectly fit all 209 primers when the are all different lengths from the different co. Not to mention variances in the same makes. Remember the shot shell is very forgiving!

The Breech plug you have in your guns was originally designed to light Black powder or one of the later substitutes, (The origonal substitute isn't supposed to be talked about.) All the designes will work well with straight old Black powder and caps. Now IMHO some %*&^%)( fool comes out using 209s in a Black powder gun and all kinds of variables come into play.

It is the gun owners choice as to what powder they use.

IMHO A good breech plug design is one that has all the attributes of the Savage BP. and Sabotloader has also discovered this and has nice photos posted.

1, replaceable vent liner, for consistency!

2, 5/32 dia. Flame path to vent.

3, Tightly fitted - seated, primer in it's chamber.

Now even this design can be changed for specific purposes, My Knight T-bolt was designed for Musket caps use. I choose to convert to 209s so I could use BH209. I am currently using the same BP that comes standard in the Vision. I have no use for plastic jackets. This plug is not stock anymore. It has a savage style vent liner installed and that is ressesed .6" from the tip of the plug, this leaves a .375 x .6 chamber in the nose of the plug. The Flame pathe is just .75" . IMHO this is a great setup for BH209. This plug setup is designed to hold and fire a Win. 209. The Only other primer that the bolt will close on is the Rem 209 4. all others are to long. The Rem 209-4 is .014 (Average) shorter than the Win 209. This is with all my current inventory, yours may vary, we are talking 209s, they aren't made to a very tight standard Period! Remember Shot shell technology and tolerances.
The 5/32 diameter just happens to be one of the sizes needed or available to thread for 10-32 threads, the savage vent liner is a 10-32 threaded screw. The carbon from the primers builds very hard. to clean the BPs simply run a 5/32 drill down threw it to your vent, if it isn't removable.

What is the purpose of having a vent in your 209 breech plugs even the fixed vents from the factory?

Why isn't the powder allowed to set right on the face of the primer?

I have shot my t-bolt with light loads and with out a vent installed, just using the 209s with an open 5/32 hole in the BP. The Rem 209-4 will fire BH209 just fine in this setup. In a shotshell the powder sets right on the face of the primer. Do you know why? Sabot loader explanes it very well it limits the amount of presure that is forced back to the 209, they are only designed to stand the pressure of Shot shells something much less than the PSI. of a Heavy sub load.

Yes, There are many different dimensions/ types of Breech plugs.

Most were designed to light Black powder, you/we choose to use something else.

I hope some of this makes sense, Sabotloaders photos should help.

SteveBNy

Great questions Ken!
Be interesting to hear some opinions - I'm not experianced enough to have one.

coal hollow

I know I keep harping on the apex but it's really worth checking out they're bp. With w209 primers blowback isn't minimal, it's completely non-existant

Screwbolts

"What is the purpose of having a vent in your 209 breech plugs even the fixed vents from the factory?

Why isn't the powder allowed to set right on the face of the primer?"


IMHO, The vent Hole / vent liner limits the amount of gas pressure that is forced back to the 209. In the Micro/milli seconds that the load fires and pushes the projectile up the bore, pressure is built in the barrel side of the vent and is above the operational design criteria if a 209 primer.

The vent is an orifice that restricts the passage of gasses going back to the primer side of the orifice. Because the High pressure only lasts Milli seconds, the pressure passing threw this orifice into the flash hole/channel can't rise above the limits that the 209 can contain.

All shot shell primers, hence 209s, are only designed to stand the pressure of "Modern Shot Shells", something much less than the PSI. of a Heavy sub load.