I absolutely have no experience with these, but was curious as to what mechanisms define these two options and the differences that make them. Could an ejector system that assists in the opening be considered assisted opener or potentially self opening, or is it a mechanism that is part of the receiver and functions as part of the internal mechanism in the action?

Examples of a partial self opener or assisted opener are the ejector Model 21 and the Cogswell and Harrison Avant Tout.

Isn’t the difference that a true self opener will open if held horizontally and sideways, I.e. not using the weight of the barrels to fall open.

You can throw the H&H, Boss, and Smith (Churchill) systems into the assisted opener category as well. They aren’t “self opening” systems.

The Beesley action Purdey is a true self opener, it springs open whether fired or unfired. The H&H system opens crisply when unfired but if both barrels have been fired it needs a little help to get started and then accelerates. I have seen a Boss, where the ejectors push against the breech face, but didn't get a chance to use it. Likewise the wrist breaker boxlock.

The Beesley designed Lancaster “wrist breaker” in both sidelock and body action versions, most definitely falls into the self opener category.

The standard Boss is not a true self opener. However, Boss did make a (relatively few) self openers.

The Beesley (Purdey) type action has been used (in small numbers) by quite a few makers in the UK in addition to Purdey (who have made in excess of 15,000). These others include Henry Atkin (a few 100 "Spring Opener" model made), John Dickson, Churchill, P.V. Nelson, Peter Chapman, Watson Brothers, Charles Hellis, Hartmann and Weiss, Symes and Wright, Holloway and Naughton, Joseph Brazier and also possibly Charles Boswell, William Evans, Charles Rosson, Stephen Grant and Terry Smith.

Outside the UK, AyA (around 40 model Senior made), Ignacio Ugartechea (model 1040), Victor Sarasqueta, A Francotte, Brancaert (Belgium), Joseph Defourny (Belgium), Jules Thonon (Belgium), Tula (a gun presented by Nikita Kruschev to Harold MacMillan (?) was sold quite recently, Baikal and O Geyger (possibly made by Bernard Merkel’s workshops in Suhl as model X).

Note that I have only seen written details in many cases, though I have seen photographs of some. This list will be far from definitive as a number of makers have made only one or two examples. the Beesley action is reputed to be very difficult to 'get just right'.

There are a few WR drop lock assisted openers WR self opener.

Ken

Thanks guys, that clears things up a bit!

The Purdey just takes a little effort to close. The "Wristbreaker" gives the impression that you are breaking something inside the action.

No it doesn’t. Idiotic statement.

One man's opinion of them:

https://www.vintageguns.co.uk/magazine/lancasters-writsbreaker

It’s Eightbore’s opinion of the guns and Just because it doesn’t jive with your opinion doesn’t make it idiotic. Jeez

No. It’s idiotic and obvious he’s never operated one. Anyone who’s used that version of the Beesley/Lancaster action knows that statement is misleading and dumb. Stiff to close, yes. You think F. Beesley would design something & patent it and sell it, HAA Thorn (Lancaster) would buy the patent, market it, and promote it if it felt like you were breaking something inside the action everytime you closed it? Nah, me neither. If that was the case it would’ve been a commercial failure, which it wasn’t. Opinions can be ill-informed. If he doesn’t like the gun, because of its designs, aesthetics, etc. I’m ok with that. Just say that, but don’t go poppin off saying something that’s bs.

Stan, there’s so many problems with that article. He describes the gun he’s using as sloppy when open, neither of my examples are like that, I’m not quite sure what he’s talking about. Maybe the gun he was looking at was worn out and completely off the face? The Lancasters mainspring is about the easiest spring to make when it comes to complex spring opening actions. That’s not saying it an easy spring to make!! Compare it to a Purdey mainspring. The Purdey mainspring is much more complex to make. In regards to finding a guy to make one if one breaks….good luck finding a guy to make ANY spring. Nobody wants to do it anymore. My body action gun broke a mainspring about 10 years ago. My good friend made a new one, it cost me $1000. I doubt he’d be excited to make another one. He wouldn’t even attempt to try and make a Purdey mainspring and his guy who used to make them had been deceased for over a decade now.
The one part on the Lancaster that does worry me are the ejectors. Lancasters, especially older ones used Perkes. The springs in the Perkes system are its weakness. Small. Complex. Proprietary design, nothing off the shelf about them. Once they go, I’m not sure who I’d go to for a repair or if my guns would just turn into extractor guns.

This is an “early” type Lancaster mainspring with hook style cocking dog, later versions did away with the hook and went to a simpler “nub”. As you can see, it’s not all that complex, but there is some intricate filing and finish work that’s required. The pictured spring is not finished. This one spring does all of the cocking (it also acts as the cocking limb in the action) and provides the power for the self opener. It’s obviously not as complex as a Purdey mainspring.

Okay, here I go with a question that to me is NOT dumb. Just ignorant of the true definition of a "self opener and assisted self opener." Will someone please explain to me with a degree of courtesy to one asking a question that is usually shown by most on this board just what exactly IS a self opener? Does it just open after both barrels have been fired or does it drop open with the actuation of the opening lever.......What?? Thanks in advance for an answer. I have to admit I have seen this phrase applied to guns for years and have always wondered what it meant but never asked until now. Forgive my ignorance on the subject, but I would now really like to understand the term. Thank.

A Beesley patent (Purdey is perhaps the best known 'true self opener'. Push the opening lever, and it opens smartly, ejecting any spent cartridges if applicable. No manual pressure is involved, and for a right handed shooter, this can be done whilst the right hand holds the gun at the wrist - meanwhile the left hand is getting the next one or two cartridges from the belt/pocket.

Video here.

Here's a look inside the RH lock of a Purdey Spring Assisted opener.

The Mainspring being a V spring normaly in most locks does not make use of the upper arm of the V.
That arm is secured or blocked into position inside the lock allowing the lower arm of the V to flex/compress and provide power to the tumbler/hammer.

The Spring Assist Opener takes advantage of that Upper Arm of the V spring.

By using a separate linkage, it compresses that Upper Arm upon closing the bbls.
The linkage generally includes an 'arm' on each side of the bbl flat that lays flat on the bbl flat. But that pivots upwards under that compressed spring tension from the lock on that side.
As it pivots upward it pushes on the bbl flat(s) and opens up the bbls for you when the thumb latch is opened.
These 'arms' are actually the Cocking Arms of the action as they re-cock the lower arm of the mainspring as well which powers the hammer in the lock.

You pay for all this novelty convenience when closing up the bbl's. A lot of spring compression going on.
So the effort is noticeable for sure but your gun handler shouldn't complain.


Here's those pics of the inside of the locks.

That upper curved 'shoe' is in contact with the cocking-rod that travels thru the frame forward and then contacts the 'arm' I noted above (one on each side of the action flats).
With the upper arm of the mainspring tension pushing on the rod, transfering tension to the 'Arm',,as soon as the thumb Latch is opened,,the bbls are Spring Assisted Opened for you.

LeFusil's comment that Eightbore has never experienced the wristbreaker is not true. The fact is that Eightbore has operated the wristbreaker and like other posters, as well as the Vintage Gun commenters, have the same opinion. Not that I would not own a wristbreaker, but there are many other guns that operate more smoothly in the hands.