I have owned a Marlin 336 with a 4X scope mounted on it for many years. The rifle was a factory package deal and it came with a hammer extension mounted to accommodate a right-handed shooter. It can be reverse to accommodate a left-handed shooter. The low mounted scope presented a challenge for when I used the rifle on the left side, and special care was need when cocking and de-cocking the rifle.
I recently mounted a Burris 2-7x35MM scope in high rings on the rifle to clear the oversize power adjustment ring. This provided extra clearance for the hammer but I was still at a disadvantage when switching shoulders. I need an ambidextrous hammer Extension.
The closest I could find on the Internet was the Carlson’s Hammer Extension. I found one in sporting goods store. My first impression was that it appeared to be will made, simple, and it was large. I would have preferred the Black Model, but the only one I could find was silver and I bought it.
http://sporting-goods.pricegrabber.com/gun-care/carlsons+hammer+extension/p/1654/form_keyword=carlsons%20hammer%20extension/rd=1/mode=ink_kwfeed_18/skd=1/st=query/I had to modify it to properly fit on my Marlin. When installed as is on the hammer it will not clear the stock. I had to put the extension in my vice and file the lower half of it down.
The other problem is the Allen screw that locks the extension to the hammer runs in from one side and the extension mounts slightly off center. This not a major problem, and I can live with it. I mounted the extentionion with the hammer in the cocked position and there appeared to be proper clearance. I realized I had a problem immediately when I tried a function test, as the bolt slides back it contacts the hammer and pushes the hammer down slightly. The thickness of the hammer extension caused the rifle to lock-up. I removed the hammer extension and file additional material off the bottom.
Another problem I found was that the extension was not tight on the hammer. I needed a shim to tighten it up and an “L” shim was better then a flat shim. I cut a shim out of the outside edge of a plastic coffee can lid.
I re-installed the extension, and conducted a number of function test. It functioned without a problem. I put a drop of Blue loc-tite in the Allen screw hole, and ran the screw in and out a few times before tightening it down. I ran a number of function tests and did not encounter a problem. The rifle functions when levered, and cocking and de-cocking works without a hitch or slippage.
The next test weather permitting will be to fire the rifle from the shoulder and lever rounds into the chamber from the magazine tube.
