In my experience, a machine rest eliminates the human error element, enabling the shooter to determine the accuracy of the handgun with different loads at different distances. In my view, it is impossible to determine the inherent accuracy of the gun since its performance is dependent upon load and range.
When a shooter sights in the gun, the peculiarities of the individual's handhold, etc., must be accounted for, which the machine rest cannot do.
Have you noted much difference in point of impact from the rest to hand held? In other words, if one zeroed the gun in the rest, will it still be zeroed hand held or is some correction required for final zero? I believe thats what you are meaning in the last paragraph, but how much difference is there?
Last edited by Malamute; 08-02-2018 at 11:51 AM.
POI person vs machine would vary from person to person, and from rest to rest (depending on the friction/spring setup).
IME quite offten different persons have different POI with the same gun, even if they have good technique and don't pull/push/twist the gun while firing. Everyone grips the gun differently and have different hand/wrist/arm strength.
Full size semiautos tend to be more forgiving, since the bullet exits the bore while the slide+barrel are recoiling and only exerting pressure against the recoil spring, hammer (mainspring) and friction on the frame. Full recoil on the hands/wrists/arms is only felt when the slide impacts the frame at the end of the extraction stroke.
Small, light revolvers or magnum ones with heavy loads are the handguns that are more sensitive to individual POI variations. The cylinder is rigidly tied to the frame, and they have a much higher bore axis. The barrel of a revolver is actually pointing down when the line of sight is horizontal; the muzzle rotates up while the bullet is traversing the barrel, and is pointing up at the moment of exit (to compensate for drop at the distance the handgun is sighted in). This is the reason while light bullets (that normally have less time on the barrel) have a lower POI compared to loads with heavy bullets, even if the later have a heavier recoil. And this is also why 38 spl loads print higher than 357 mag loads in a revolver.
Last edited by TiroFijo; 08-02-2018 at 12:33 PM.
Yes, I'm just curious how much difference Oldhat12 has noticed from machine rest to hand held.
Instead of the grip being the interface between the pistol and the rest, I wonder if there isn't a way to use the light mounting rail. You'd still need to allow for recoil to keep from destroying the frame, but it seems like you should be able to clamp the pistol into the rest using the rail.
Okie John
“The reliability of the 30-06 on most of the world’s non-dangerous game is so well established as to be beyond intelligent dispute.” Finn Aagaard
"Don't fuck with it" seems to prevent the vast majority of reported issues." BehindBlueI's
Rail in rest sounds interesting
My FLG always wanted to mill Ransom inserts out of aluminum or hard Delrin to fit an individual grip frame, he did not like the rubber inserts.
We once got very fine accuracy by aiming the gun for every shot with a scope in V blocks on top of the slide to do away with slide to frame and frame to insert fit.
Too bad, we lost the range and its concrete rest base.
The old Phelps machine rest held a revolver by the barrel, upside down. Great alignment, but you sure weren't going to zero the sights.
Gun Tests magazine once clamped a Casull in the Ransom Rest. Bent the grip frame with full charge .454s.
Code Name: JET STREAM
I think this must be absolutely vital to getting best results.Originally Posted by Jim Watson
Okie John
“The reliability of the 30-06 on most of the world’s non-dangerous game is so well established as to be beyond intelligent dispute.” Finn Aagaard
"Don't fuck with it" seems to prevent the vast majority of reported issues." BehindBlueI's
The main difference I notice is that the groups are much tighter with the machine rest than with a human hand doing the firing. The grip of the rest on the gun is far more consistent from shot to shot, and the possibility of flinching is eliminated. The greater the distance to the target, the more other small factors such as wind, humidity, etc. can influence individual shots.
Since the rest has both windage and elevation adjustments, it is possible to adjust shots into the 10 ring with a gun regardless of the accuracy of the sight picture. How can one tell whether it is the rest adjustments or the sight adjustments that are being sighted in? While you can manage to get all shots wherever you want them on the target, they are not necessarily going to be in the same place when you change over to hand held shooting.
I think the machine rest is best used for seeing just how small of groups you can produce with different loads. Use a sandbag or the equivalent for sighting in the gun.
All this said, a machine rest is a hell of a lot of fun to use, and for most of us isn't that what this is all about?
First, I have to apologize for my bad english. since i'm a shooter from germany this is not my mother language!
I hope you can understand me anyway.
I shoot a mg2e and I want to build a ransom rest.
This contribution is very interesting for me! a colleague gave me his original ransom rest for tests.
Now I'm considering if I disassemble the original ransom rest and rebuild all parts which is very complex.
your machine looks easier. do you have plans for that?
would be particularly interesting synonymous as you have the clutch built so that the pistol can shoot when shot up.
the rotation must also be slowed down.
many Greetings
Wolfgang
My goal in making the machine rest shown above was to use standard off-the-shelf parts wherever possible to reduce time and work. I have no plans, but the pictures pretty much tell it all.
I used industrial pillow blocks with a 3/4" bore, and made a 3/4" cold rolled steel rod with a keyway along its length. The pillow block set screws tighten down in the keyway to prevent slipping. I made leather washers that ride against steel plates with the valve springs producing the friction. This can be adjusted by tightening or loosening the spring pressure. Knobs on threaded rod sections control windage, and an elevation adjustment screw is at the front. Other than that, there is not much to it. I have shot everything from a .22 to a .357 magnum in it, but I don't know why it wouldn't handle something heavier.
It's considerably heavier than a Ransom Rest, but I believe it is more rugged and equally precise.
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