Breach plug design.

If you stand back and look at it, the stock Savage 10ML-II plug is tough to beat. The crew at Savage took Henry's design and took it farther. They should have came up with the hex head from the start was the only flaw IMO. It's just not a matter of taking the higher pressure safely but also the ease of manufacturing and fitting. It's, it's' it's like butter!

Now RB's 5/8" inch plug is a simple one also and if you had to you can take a 5/8" USF grade 8 bolt and use a drill and a file to make one.

Thanks for moving it wilmsmeyer.

I agree with Rossman40. What's wrong with the Savage plug? Some say it doesn't have enough thread. Whenever the length of threads equals or surpasses the diameter no real benefit is gained. Some say it is too long. To make the DD and DMB barrels for the 700ML's, hunter smoker nose was made .085" longer to combine with the Savage plug so the tip of the plug is at the meat of the barrel just barely past the lug to make these guns extra safe. Some of that length is also a safety factor in a properly chambered barrel (long story but the guru's on here know why). Some say make it from stainless. If you take care of a gun at all a Savage plug shouldn't rust. Stainless steel is much more likely to gall and stick. Some say the flame path is too long. who's having misfire issues? Some claimed better accuracy with recessed ventliners. The topic has seemed to die. When someone is having accuracy issues, does the suggestion to recess your vent ever come up? Has anyone on here other than me had to remove a stuck recessed vent? It's not very easy to do it right. I say Savage plugs are perfect for most needs.

Just spent over an hour removing stuck vents from Herman's two recessed plugs . Carbide drill bits help
Richard

I have to agree with Edge, it is kinda of a balancing act of volume behind the vent, vent size and chamber pressure, maybe even duration of pressure. Your goal is to limit the amount of pressure on the primer, which if your using a 209, might not take full chamber pressure since it was designed for low pressure shotgun shells.

Another factor nobody may have seen is pressure on the bolt. If you were to get full chamber pressure of say 40k on a 209 your looking at just 2k on the bolt. Considering on a 10ML-II or a 700ML there is no bolthead lugs, your relying on the bolt handle to take that pressure. A failure could result in the handle breaking or the bolt being forced open, bad,,, bad bad. It is not to say everyone should only use centerfires with bolthead lugs, I'm sure the design of both the 10ML-II and 700ML could probly take 4 or 5 times that before something breaks. Just not a steady diet of pounding. I've only heard of this happening once. Even guys that have ruptured barrels the bolt remained closed. It is a small thing in the big picture of design.

I think If we design a better sealing plug and keep the plasma going in the right direction (down the barrel and out the muzzle) we can get rid of those pesky vent liners. Nula and Bad bull are good examples of what I'm saying. ;D ;D

You will not totally get away without a vent. The vents secondary purpose is to hold the powder without a primer installed. I would feel uncomfortable loading a primed weapon.

If you look at the better systems using a cartridge case, there is Pete's plug, then there is the Ultimate/BP Express and the set-up Mountainman, or was it the early Hunter kit, was selling using the .32 ACP case. Then there is Cecils at PR using the 25 ACP. All of these rely on pressure forcing the case walls out to chamber walls to get your seal, not a nipple against brass. Just one time you get a flame cut your pretty much done because the gas /plasma jet will only get worse. Path of least resistance..

If you don't like changing vents then use a carbide bushing, a ceramic bushing, or a fouled plug.

All three work for extended periods of time, I normally use a combination of two of these since I rarely clean my plugs ;D

edge.

If you are replying to my post then we are far apart!

Cleaning the flame channel increases volume and it is this volume that increases vent liner wear!

In the second sketch below I only clean enough to remove the shape of the primer from the primer crud...but that is just me.

edge.

FROM THE TIPS SECTION

A sketch of the breechplug with some dimensions:



A sketch of a badly fouled breechplug. If the fouling becomes bad enough the carbon crud
will take on the shape of the primer and the bolt will become very difficult to close:



A sketch of the relationship between the Boltface, Primer, and Breechplug :



Here is a sketch showing the relationship between
the Savage Barrel, Breechplug, and Barrel Nut:



If these are too large send me a PM and I will shrink them. Dimensions may not be exact
but are very close and for informational purposes only

edge.

PS this is a locked thread for pictures and sketches only!
If you have something that should be included please sent it in a PM or post on the
board and I or another Moderator can add it to this thread.