Std and MK 1 semi auto pistols

Question that has been stalking me for a long time. It is : what exactly was the reason or reasons and what change occurred from the A54 frame to the A100 frame? I have not found an answer that settles the matter for me.

That is a good question!!
Maybe they wanted the grip medallion on the ejection port/serial number side of the pistol.
But the real reason might have something more to do with the magazine button, which switched to the left side.
Chet15

And to your reply, thanks! But! Why change the frame that required a lot of other changes as to the mag follower thumb piece from one side to the other ? Grip screw location. One question leads to another for which I cannot find an answer. Obviously a lot of engineering changes involved in this redesign. I fear there may not be a clear answer due to time lapse. And now, another question: why did the engineers change the finger grasping knobs on the bolt from straight to tapered and then back to straight and then back to tapered? Change for change sake? Probably not. Questions. Questions.

I believe it was in preparation for them going to the Mark II< with the hold open lever on the left side ,so they had to more or less "flatten" out the frame on the left so as to put all the mechanism lever , pin ,etc to hold "open" the bolt on the last shot...this was not well liked on the RST or Mk I as the when was the "last shot" and "was gun loaded or not"??? used to watch guys at the range and see just what they did,,,,most just pulled the trigger..... :shock:
by the way this 'hump", the follower button rides down the frame is what can cause "drag" on the use of Mark II mags in the Mark I (Rst) as the button is wider, to work the hold open lever on the Mark II guns but at times will drag on the inside of the frames "hump"......yes the hump was on the left for the A-54 frames and moved to the right on the A-100 frames....this also affected the lower grip screw hole location, swapped sides,lower on the left panel A-54, and then the opposite for the A-100..
lots of thought and engineering went into these early guns,,,look at the process they did for the "safety" update " to the old models.....BIll R had them boys using their heads for other than a hat stand..... 8) :roll: :wink:

Dan: I have had about the same thoughts as you regarding the changes on the A54 grip frames. I still can't quiet grasp the question: why? I understand crowding everything into the left side of the receiver. I understand the evolving changes that occur in a given model over the lifetime of a particular piece. The basic design of the first auto pistol has remained , for the most part, unchanged. This means that Bill Ruger got it right the first time; just like the M1911. Some seventy years for the Ruger: one hundred years for the Browning design. Overall , no secrets from Ruger will be forthcoming, I am certain. Just seeking answers to satisfy my inate curiosity. Looking for answers.

I've never met an engineer who said it's perfect we're done. Without the changes there would be nothing for the engineers to do - or a reason to keep them on the payroll. Some changes may have been for manufacturing ease. All the changes were to address some perceived inadequacy of the original design.

rugerguy said:

I believe it was in preparation for them going to the Mark II

Click to expand...

Possible. But the change to the A100 occurred in about 1971. The Mark II came out in 1982.
Chet15

Good point on the year of the A54? Frame change and the near eleven years between the model changes. Again, Bill Ruger got it right the first time the Std model was introduced in 1949! And, as I stated earlier, the frame change required a lot of other changes to the Std and MK1. New does and tooling, etc. A lot of expense for a company to undergo. But Ruger was, by that time, a made company and funds were not an issue. Why the change still lingers.

If my faded memory is right,, I recall reading somewhere that WHEN the change was made,, part of it was due to the machine plates that stamped the frame halves were worn, and they were having to replace them.
But that doesn't answer the "why" the changes were made, because they could have just duplicated the A-54.
As noted above, the magazine button, a person holds the magazine in his right hand, to depress the button as he's loading. Feeding bullets with his left hand. The A-54 type,, makes this more awkward. And as Dan mentions, the engineers may have been looking at changes for the bolt hold open etc long before production happened.
Remember,, often,, perceived problems, (complaints) by people often drive changes in an item.
Look at the grip frames on the SA's. From XR3 to XR3_RED, to the Dragoon. ALL of those changes came about because someone convinced Bill that things could be "better."
And if you study all 4 models of the MK series .22's,, most of us prefer the MKII over all the others.

The comparison of the Browning 1911,, it too had mods early on. From the 1911 to the 1911-A1. And then look at the current crop of 1911's. Most folks prefer a version of the A1 with other mods over the original design.

Evolution due to customer input.

Just my humble opinion.

RG: your input was great and appreciated. You got to remember, however, Bill Ruger controlled his company with an iron fist and it was, he, who approved everything! In the mind of a genius, one can only wonder how far ahead of everyone else Bill Ruger was in terms of changes. Different models and designs and the list goes on. In reality, we may never know, for sure, why the design change was made when it came about.

Just as I asked early on in this thread why the finger grasping knobs were straight, then tapered and back to straight and then back to tapered on the bolt. I like the taper; not as painful to grasp and retract the bolt. But why back and forth so many years ago?

More facts to emerge, I hope.

I read the tooling was worn. It may be in RL Wilson's book. I remember reading about this subject.

the "hold open" or "bolt release" being on the left side far preceded the Ruger company going into business and BIll R being a student, designer, engineer for all those military companies, knew ahead of time it was inevitable. hell he cut the notch in the bottom left rear of the original bolts to "manually hold the bolt open" back when he designed and built the RST-4..........he was thinking this out well before the advent of the Mark II, then of course the lawyers got involved and built the Mark III, so no surprise they had to UNDO it all and come up with the Mark IV. LIke Contender says, to me also the best of the lot was the Mark II............

as for the ears of the bolt, it was the 'extra" step of having to cut ( Mill) a taper in the ears, and as the story went for the Korean war effort to save steel they pressed on a separate piece, instead of milling down a 2 inch piece of bar stock, complete was of steel....now days they could cast it,,,they cast everything else and other companies are using "MIM" ( look it up ,too much to type out...) 8) :roll: :wink:

All of the above make perfect sense & I would say are part of the real reasons why
However, there is no one around to answer it fully
The guessing only continues on....................

Correct you are in that we just keep on guessing as to why the change ,which was not just a change in manufacturing the frame, but caused a lot of changes in its wake, to the entire pistol. I suspect, as is well known, Bill Ruger controlled everything in his domain!
Most all that could fill in the gaps of now unknowns, are deceased. Maybe , one day, we may know more.

As far as the bolt "ear" diameter is concerned, consider that diameter was not much larger than the receiver diameter of one-inch. Drawing the bolt backward was completely dependant upon the purchase of those serrations on the bolt ear periphery. Many owners, with fingers the same diameter as ring-bologna, had a tough time grasping the bolt ears to charge a round into the chamber from the magazine, thus, when the Mark II made its debut, scallops at the rear of the receiver were incorporated so all size fingers could accommodate access to the bolt ears. And the bolt hold open device hadn't been thunk of as yet.

As far as the bolt hold open inception. During the early Vietnam War years there was a Government contract that called for integrally suppressed Ruger Mark I Target pistols using the A54 style grip frame. These pistols were used by the nicknamed "tunnel rats" who used these pistols and a flashlight to venture into the tunnels where the enemy would "hole-up". Consider how these intense moments would have a soldiers bunghole tightened up tighter than a ducks arse. After emptying 9 rounds during an encounter, at what must have been some pretty close distances, it would sorta be nice to have some indicator, that involved. "hey man, I'm empty".
Ruger Co. considers these quandaries when they're brought forth and that one may have been another reason WHY the bolt hold open device was added to the Ruger Mark II.