My dad just picked up one of these, and he commented that when the action screw closest to the trigger guard was tightened up, the bolt would bind. I removed the bolt (safety held forward, trigger depressed) to take a look, and now I can't for the life of me figure out how to get it back in. Seems to be an issue with getting all of the lugs properly aligned...is there some trick to doing so?
Insert the bolt part way until it stops. DEPRESS THE SAFETY. You might have to move the bolt slightly up and down. It should go in easily. Also, the front part of the bolt rotates, so the front part has to be lined up so that it is in the proper position,---that is, with the flat side downwards and the rounded part of it on top. The lugs are farther back, and can be easily seen during the insertion of the bolt.
Early Remington 540 rifles had a non-adjustable trigger. Later ones had a trigger that can be adjusted slightly for sear engagement, weight of pull, and overtravel. A fine rifle, and usually very accurate.
These evolved from the Remington 581 series, which is basically a mini-788 rifle design. They had a second action screw where the 581 series had only one.
Also, if you have taken the bolt apart, or moved the firing pin, then it will not go in the rifle. The sear on the firing pin and slot in the end cap should be at the very small notch in the back of the bolt body, and in line with the milled slot in the bottom of the bolt. If the firing pin / sear is in the large notch close to the bolt handle, then take the bolt handle in your left hand, and with the flat of a screw driver, pull backwards on the sear / firing pin and twist it so that the sear goes into the correct smaller notch.
If the rear action screw is binding on the bolt, it is possible that someone over tightened it and compressed the wood, or that it is too long. A few minutes with a stone should shorten the screw enough so that it does not bind, but be careful and patient. Another solution might be a thin washer underneath the head of the screw. The over long screw might even be your problem, so if the above fails, then loosen the screw off a turn or two, and try inserting the bolt.
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