I picked up another Mossberg 342 this weekend, the top one it is a 342 KA. It needed more than a little attention but looks OK now.
The bottom one is a 342 KB
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Here is a thread starter on the 342's. There is not a lot of information about them. I got this info from looking at old advertisements, photo's and parts manuals.
Feel free to add to it.
Mossberg created the 300 series line of rifles in 1958. The series took advantage of a new bolt design and the use of a new magazine, number R1220 also called the Magic Three Way Magazine as the design allowed for the use of short, long and long rifle cartridges. Another new innovation was the AC-KRO-GRUV barrels. These had 8 shallow grooves made by pulling a carbide swedge through the bore. Mossberg started using these in 1960 when they advertised, "New Ac-KRO-GRUV" on the Palomino & 340B. AC-KRO-GRUV was registered as a trademark 7218296 on 12-2-1963.
The 342 series was a carbine with 18" barrels, sling swivels and a cotton web sling. All had the Tenite Folding Extension Grip. The Folding Extension Grip was made of wood from 1948 to 1955 then black plastic (Tenite) from 1955 to 1970's. There were 18 models that used this feature. All 342's had Monte Carlo Stocks, Most were Birch with a walnut finish. Most had white buttplate spacers.
Scopes: One of the last scopes Mossberg made was the M4D 1952 - 1965. That would be correct for some of these 342's. Weaver rimfire scopes were popular and plentiful but the "tip-off" mount could not be used on these as the dovetail scope grooves were short and the mount interferes with the bolt operation.
The Models & Differences:
342 & 342 K, 1957-1960
Flat bolt handle, ribbon around center of ball, Monte Carlo stock W/round pistol grip, Finger groove trigger guard. Old style black plastic buttplates, no white spacer. R1220 Magazine. 342 had S109 front sight and S108 receiver sight & S134 open rear, held by 2 screws. The 342K used the S134 open rear and the S133 front sight. The 342K Cost $31.95 in 1958.
342 KA & 342 KB, 1960-1969
Round pistol grip early then squared pistol grip. Finger groove trigger guard early then plain trigger guard. Flat bolt handle, ribbon around center of ball early then round bolt handles W/smooth ball. Receiver cap is longer on the 342 KB. (Same Part Number) Serial numbers after 1968. D&T for receiver sights but stocks not cut out. R1220 Magazine, Ac-Kro-Gruv barrels. S134 open rear, S133 front early, then S138 front S141 open rear. Rear sight change to a dovetail with the S141. Different safety markings. Cost $44.45 in 1966
342 KC, 1970-1972
Walnut Monte Carlo stock W/cheek piece, Serial Numbers, Round bolt handles W/smooth ball, Two new types of firing pins. Magazine change to R2384. Different magazine latch, angle bar & stock plate. Receiver cap is longer. S138 Front, S141 open rear. Cost $41.45 in 1972.
The bottom one is a 342 KB
Here is a thread starter on the 342's. There is not a lot of information about them. I got this info from looking at old advertisements, photo's and parts manuals.
Feel free to add to it.
Mossberg created the 300 series line of rifles in 1958. The series took advantage of a new bolt design and the use of a new magazine, number R1220 also called the Magic Three Way Magazine as the design allowed for the use of short, long and long rifle cartridges. Another new innovation was the AC-KRO-GRUV barrels. These had 8 shallow grooves made by pulling a carbide swedge through the bore. Mossberg started using these in 1960 when they advertised, "New Ac-KRO-GRUV" on the Palomino & 340B. AC-KRO-GRUV was registered as a trademark 7218296 on 12-2-1963.
The 342 series was a carbine with 18" barrels, sling swivels and a cotton web sling. All had the Tenite Folding Extension Grip. The Folding Extension Grip was made of wood from 1948 to 1955 then black plastic (Tenite) from 1955 to 1970's. There were 18 models that used this feature. All 342's had Monte Carlo Stocks, Most were Birch with a walnut finish. Most had white buttplate spacers.
Scopes: One of the last scopes Mossberg made was the M4D 1952 - 1965. That would be correct for some of these 342's. Weaver rimfire scopes were popular and plentiful but the "tip-off" mount could not be used on these as the dovetail scope grooves were short and the mount interferes with the bolt operation.
The Models & Differences:
342 & 342 K, 1957-1960
Flat bolt handle, ribbon around center of ball, Monte Carlo stock W/round pistol grip, Finger groove trigger guard. Old style black plastic buttplates, no white spacer. R1220 Magazine. 342 had S109 front sight and S108 receiver sight & S134 open rear, held by 2 screws. The 342K used the S134 open rear and the S133 front sight. The 342K Cost $31.95 in 1958.
342 KA & 342 KB, 1960-1969
Round pistol grip early then squared pistol grip. Finger groove trigger guard early then plain trigger guard. Flat bolt handle, ribbon around center of ball early then round bolt handles W/smooth ball. Receiver cap is longer on the 342 KB. (Same Part Number) Serial numbers after 1968. D&T for receiver sights but stocks not cut out. R1220 Magazine, Ac-Kro-Gruv barrels. S134 open rear, S133 front early, then S138 front S141 open rear. Rear sight change to a dovetail with the S141. Different safety markings. Cost $44.45 in 1966
342 KC, 1970-1972
Walnut Monte Carlo stock W/cheek piece, Serial Numbers, Round bolt handles W/smooth ball, Two new types of firing pins. Magazine change to R2384. Different magazine latch, angle bar & stock plate. Receiver cap is longer. S138 Front, S141 open rear. Cost $41.45 in 1972.
