Bad Breechplug, Bad Muzzleloader;
Good Breechplug, Good Muzzleloader?

By Randy Wakeman

After some twenty years, during which the sport of modern inline hunting and shooting has enjoyed unprecedented growth, it seems that many manufacturers remain clueless when it comes to good breechplug design. This is at once amazing and perhaps even shocking, as the breech plug is what differentiates a muzzleloader from a breechloader, or a piece of pipe. Yet, despite the obvious importance of the breechplug to retain our percussion device and (hopefully) keep primer material from burning scopes, fouling actions and singing our faces, good breechplug design has eluded manufacturers.

What we have seen is a cumbersome, reactive approach to breechplugs that has all too often been a band-aid approach without any forward-looking consideration given to different propellants and projectiles. Rather than bad engineering, it has been essentially non-engineering. Many muzzleloading rifles operate with a degree of clumsiness and filth that would be quickly and loudly be deemed completely unacceptable in any other type of sporting firearm. Much of this can be traced to hard to manage, spectacularly filthy breech plug design.

As long as the presumption was that the entire firearm was completely disassembled after firing, as still suggested in some owner’s manuals for a full and complete cleaning in a timely, if not immediate manner after firing, the filth of the breechplug was just considered another filthy part to clean. Before it became clear that scope use was the defacto preferred field application of inline muzzleloading on the basis of safety and accuracy, scope burning was of little import. That changed, as we all know, in a big hurry.

Now, the ill-prepared muzzleloading manufacturers used a variety of awkward devices just to “cap” and “decap” breechplug nipples. These cappers required some finesse to use at all, much less in field conditions when access to the breechplug is made more difficult by the presence of scope, bases and rings.

It is obvious that #10 caps, #11 caps and 209 primers are all percussion igniters. That’s how they work; no percussion to initiate ignition, no bang. However, propellant options changed and the inadequacy of caps became self-evident to muzzleloading enthusiasts.

Some muzzleloaders, now gone from the market, were produced by major gun-makers just to show that they could, an attempt to piggy-back on the widespread enthusiasm of inline muzzleloaders generated by Tony Knight and Doc White. The Remington 700ML failed, as did the Ruger 77/50.

Pyrodex pellets happened. Much harder to ignite than loose powder, they were (and are) produced with an igniter pad at one end, little more than black powder. Load the pellets upside down in a #11 cap fired inline and misfires were commonplace. Without thinking things through, musket and 209 nipples were added to try to solve the ignition issues. Some did, some didn’t, but the attempts that were “successful” were even more so in blowing flaming primer crud on scopes, into actions and onto shooter’s faces. My face is one of the many where flaming grit hitting my face made me wish I’d popped on my motorcycle helmet and not just shooting glasses. I wanted to shoot muzzleloaders, not don my “Nomex Warrior” regalia. Others felt the same.

It got worse. In 2002, Triple Se7en powder was introduced, followed quickly by Triple Se7en pellets. Both products were harder to ignite than their Pyrodex predecessors. There was no "ignite pad" for T7 pellets: it was 209 primers only and not all 209 primers worked well. Pellets made #11 caps obsolete overnight.

Pellets, never a good idea for the best accuracy, displayed anomalies of their own. Underbore conical bullets (Powerblobs) gave us a new problem: the launching of flaming pellets into the air, for undersized bullets that rattled own the bore could just as easily rattle right out. Sabots, with quick-obturating relatively soft durometer polymer blends solved much of that, but hellfire from crummy 209 breechplugs still blasted muzzleloaders and scopes with flaming crud. It seems that more primer fire shot back and out the sizes of some breechplugs than made it through to ignite the powder.

I’ve got nothing against nipples; heck, I was raised on those things. When we blow flame at a nipple, whatever can made it through does, but the flash hole does not begin to flow the full amount of the primer ejecta. Nipples became obsolete. Knight rifles tried to address the issue with “Full Red Plastic Jackets.” Not a bad idea, but a compromise adding more hassle (pre-priming the primer) while still allowing enough grit and crud into their actions to make actions hard to work after a dozen or so shots.

Thompson added “209 holders” (Flamethrower Nipples) that were aptly named, retaining significant spewage. Austin & Halleck inlines used the T/C nipple and their guns were quickly fouled with 209 crud as well. CVA, the invariably copyist, used cheap wire retainers that often broke to try to hold 209's in a fashion similar to T/C. These spewed 209 crud with gay abandon in their poorly made Hunterbolt and Firebolt rifles, ruining more then a few hunts in the process. If all this sounds like a mess, it was.

In 2001 and 2002, a couple of more practical designs appeared. The Thompson Omega killed the scope baking and though there was some internal blowback, it was easily wiped away from the sealing cap of the Omega’s drop action.

Savage’s initial 10ML became the 10ML-II, the breechplug that remains as this day as the finest, most efficient breechplug system yet devised. The bolt of the Savage 10ML-II holds the 209 against the breechplug primer pocket, “controlled primer feed” for lack of a better term. Upon ignition, the 209 primer instantly puffs, effecting an instant seal. All the material needed for instant, positive ignition goes into the breechplug. No bolt fouling, no scope baking, no external fouling at all and no internal fouling, either. Primer residue is a fact of life; any excess is retained inside the Savage 10ML-II plug where it belongs. Not on your scope and not on or in your action.

Meanwhile, we have had other attempts. Large primer holders that blow crud against the breechplug in the H & R Sidekick, an otherwise solid gun now discontinued. Magnetic breechplug attempts by Lyman in their imported “Mustang” that is another filthy mess. Knight attempts in the “leakmaster” Revolution with plastic jackets and nasty gunk in the Knight non-red-plastic jacket plugs found in the KRB and KP1.

The interrupted thread speed breech found in the T/C Encore is clean, but the “Speed Breech XT” currently offered only in the T/C Encore Endeavor and T/C Triumph is the best offering in many years. It is NOT “self cleaning,” as stated by T/C. Carbon builds up in them, just as in the Savage 10ML-II, as it should.

So, yes, good breechplugs are part and parcel of good muzzeloaders, a critical component that should not be ignored. I’ll list and grade the best of them.

    Savage 10ML-II: GRADE = A. The best, with a replaceable flash hole (ventliner) that gives the breechplug indefinite life.

    Thompson Speedbreech XT: GRADE = A. Hand removable, it is exceptionally clean.

    Thompson original Speedbreech: GRADE = B+. Not that handy, extractors that swivel can be a hassle, but still a cleaner breechplug than most.

    Thompson Omega / Encore / Contender: GRADE = B. Still better than most, perhaps most appropriate for the Omega, but still better than most breechplugs other than the Savage 10ML-II plug and T/C’s own Speedbreech XT.”

Also not surprising is that the Savage 10ML-II, T/C Endeavor and T/C Omega are three of the most hassle-free muzzleloaders on the market. I can’t say the same for the T/C Triumph, but a great breechplug can’t fix everything.

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Copyright 2008, 2013 by Randy Wakeman. All rights reserved.