Excerpt from my CD “Old Airguns and Memories”
Crosman M-600
Crosman M-600
Hello to all;
Crosman CO. introduced the first true Semi-Auto 10 shot magazine, CO2 actuated blow back .22 caliber pellet pistol in 1960. The Crosman Model 600, in my view, is one of Crosman’s most sophisticated designs. As I understand it there were actually some prototypes of this pistol shown at Camp Perry in 1957-1958, obviously there was a great amount of design attention and time devoted to the M-600 prior to the release in 1960. A second Model, the 677 was introduced in 1961 and designated the PLINK-O-MATIC 15 shot, which was the B-B version. The M-600 ceased production in 1970, the M-677 in 1964. Both Models utilized a single 12 gram CO2 cartridge as a power source. The M-600 .22 caliber is under review herein.
Specs on the M-600 / 677 were as follows: OAL- 9-5/8” height 6”, barrel length 5-1/16” weight 2lbs 10 ounces, adjustable rear sight, up to 40 shots per CO2 cartridge and approximate muzzle velocity 340 fps (14.3 grain pellet). Both models used a version of the twist rod swing-feed design similar to the earlier system used on the Crosman Model 400 Repeater rifle, however the M-600 utilized an internal magazine integral with the receiver as opposed to the external removable magazine on the M-400 repeater rifle, both use a spring loaded follower to advance pellets into the swing arm. The safety lever is located on the left side of the pistol underneath the grip panel it is a sliding trigger block system moving it up puts the pistol on safe. Accuracy quoted as ¾ inch @25 ft.
I might mention at this point that for consistent feeding in the M-600 it is vitally important that the pellets used must have a flat head and rear skirt diameter that will not allow the next pellet, to enter the rear skirt portion of the pellet in front, otherwise as the pellet swing arm tries to load a pellet a shearing action will take place and cause a jam. The original Crosman Super Pells were designed with head/skirt diameters to prevent this and while they are no longer available, I have had no problems with currently available .22 caliber RWS Match or Hobby pellets and they are more accurate in my experience. I have read where some folks stated they had no problems feeding domed head pellets in the M-600, may be, but it defies the mechanical logic of the system, and further if they did there would be some mighty mangled skirts on those pellets going downrange, and would I think, play havoc with any accuracy potential; healthy skepticism would be in order here. Others may disagree.
To charge the M-600 with CO2 make sure pistol is unloaded, cock the pistol by moving cocking slide to rear to engage the sear then return the slide to the forward position and push safety lever up to safe position. Unscrew the knurled tube cap piercing assembly insert the CO2 cartridge with small neck up and replace tube cap assembly and screw down as far as it will go, this will pierce the CO2 cartridge and charge the system. (Note there were two types of tube cap piercing assemblies the one described here is the fixed version and the other is the “push button” type that required a push to pierce the CO2 cartridge). After charging and before loading the pellets I always fire the pistol once to make sure the CO2 cartridge was pierced.
Loading the magazine; make sure safety is on, then retract the magazine follower knob and lock in the locking slot at rear of magazine and load 10 pellets, release the magazine follower knob to place tension on the pellets in the magazine, the pistol is now ready to fire, push safety down and from this point the pistol will function in semi-auto mode, every time the pistol is discharged it will cock and load a pellet, a really revolutionary design!!!
I have two of the M-600 CO2 pistols one in the original box with literature, can of Super Pell Pellets and also an original Crosman holster made for the M-600 (actually made in Dunnville, Ontario Canada for Crosman), the other M-600 is a standalone (no box etc.) The boxed unit is reviewed here. I picked up both of these pistols in a trade in 1988. The pistol under review was given a complete valve rebuild prior to testing. Also worth mentioning is the boxed unit was originally purchased from” Sears Roebuck & Co.“ in August of 1960 according to the literature in the box. Some may not remember, Sears sold a number of Crosman Air Rifle/Pistol products during the 60s –early 70s out of their stores.
As is my normal practice using cardstock paper I placed three ½ inch adhesive dots as targets, the target was placed @ 30 ft. I used .22 caliber RWS Match @ 14.0 grains and RWS Hobby @ 11.9 grains, five shots on each target and measured center to center shot from bench rest. The first target RWS Hobby measured 4 in 1.370” fifth shot enlarged group to 2.270” center to center, second target RWS Match measured 4 in 1.300” center to center with a fifth enlarging the group to 1.865” center to center, third target RWS Hobby measured 1.200” center to center, looks as though my M-600 is capable of about 1.25” on average @ 30 ft. Velocity for 25 shots averaged 323 fps and 3.0 ft. lbs. I took the average of the two pellet weights at 13.0 grains for these figures, velocity measured using my Pro Chrono Digital chronograph 24 inches from muzzle, a high of 383 fps to 262fps on the 25th shot.
There were no feeding failures of any sort during testing or when conducting rapid semi-auto fire testing, these pistols are a marvel of engineering for a pellet pistol made some 64 years ago, I mean think about it, utilizing CO2 not only as a method of pellet propulsion but also as the force for operating the semi-auto action, just perfect execution of a sophisticated design normally relegated to firearms, hardly a consideration for a pellet pistol in those time frames!!!! Crosman hit it out of the ballpark with the M-600 in my opinion.
I believe the M-600 CO2 .22 caliber semi-auto pistol represents the epitome of engineering design for Crosman in the 1960’s if you can get your hands on one grab it, as the old saying goes “They don’t make “em” like that anymore.”
Garey
