How to assemble a Remington 550-1?

Answer 1

http://stevespages.com/pdf/remington_550.pdf

HOW TO MODIFY SEAR CASE & ASSEMBLE A REMINGTON 550-1 :

Start with all of the parts ( EXCEPT THE EJECTOR , staked into the receiver) out of the receiver.

IF the SEAR CASE has not been modified like the Factory Modification ( removal of REAR 1/3 PORTION of Sear Lip ), perform this revision to the Sear Case FIRST :It does no harm to remove the rear portion of the sear spring case lip. I have read that many 550-1 rifles have been ruined by cross-threading the sear spring case when attempting to start the threads as it would not clear the rear of the sear. I almost did it myself the first time I worked on this type of rifle !

Screw the sear spring case all of the way into the EMPTY receiver.Mark the case towards the rear of the receiver. Remove the case. Grind or FILE a small flat on the sear retaining lip of the case. This will allow the case to go past the rear edge of the sear and start into the receiver threads. Remove about 1/3 of the Sear Lip ; this would be a crescent shaped sector of metal , up to , but NOT past the edge of the center "shaft" portion of the case; round the bottom edge in the removed area to assist the SEAR in moving past this newly formed "channel" during final assembly.

Install the recoiling chamber in the breach. Install the receiver insert assembly using the two pins.

Assemble the two carrier parts with the spring and carrier spacer bushing. Insert this assembly into the receiver from the bottom. Start the pin through this assembly and insert it far enough to retain the parts without protruding beyond the parts. Insert the sear into the receiver from the bottom. Line up the pin hole with the pin through the carrier parts. Push the pin all of the way through and flush with the outsides of the receiver. This assembly is assisted by using TEMPORARY , LOOSE FITTING , substitute pins , like small diameter wooden dowel pieces to hold parts in proper alignment during several of these assembly steps. As alternate , use of 6-penny , 8-penny, or 10-penny smooth nails is acceptable : install Factory pins when things come together properly !

Installing the sear spring case: This is the most tricky part of the assembly. Be prepared to wiggle or push the sear up OR down with a small tool or dowel to assure proper final fitting of Sear into the Modified Case Screw.

Insert the sear spring into the sear spring case with some thick grease to hold it in place in the Case. Hold the sear down against the bottom of the receiver and insert the MODIFIED sear spring case and sear spring with the flat towards the front of the receiver. BE SURE that the Sear Spring properly enters the SMALL HOLE in the Sear! Once it clears the hook on the sear, screw the sear spring case SLOWLY all of the way in. The factory staked the case to the receiver. Re-stake or use some thread locker. Check to make sure the sear can not rotate to the top of the receiver as it is stopped by the lip on the sear spring case. Install the trigger by installing the front pin and the rear pin. Look through the hole in the receiver to make sure the trigger is on top of the sear.

Install the firing pin into the bolt. Point the Rifle barrel downward to prevent the Firing Pin from falling from the Bolt , or becoming wrongly positioned inside the Bolt. Slide the bolt into the rear of the receiver. Monitor the Bolt , and keep it from rotating out of proper alignment with the Receiver Rails. Pull the trigger then push it further to clear the sear. Install the receiver plug with the action spring, action spring guide, main spring and main spring plunger. Reposition the nearly assembled action and install the safety asembly.

Install the barreled receiver into the stock. Verify all functions.

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On MY damaged 550-1 , I used the CASE to repair the damaged threads by installing it INSIDE-OUT by use of : FIRST a small diameter thread , pulling it into position through the inside of the Receiver ; SECOND , finger screwing it the first couple threads to get it properly started ; THIRD , VERY , VERY CAREFULLY gripping it on the LIP with a SMALL pair of Vise-Grips ; and FOURTH , VERY , VERY , VERY SLOWLY working the case into the threads : when the FIRST resistance was felt , I began a protracted BACK-and-FORTH process that took most of the repair time . When the Case threads finally emerged from the bottom of the Receiver , I removed the "inverted" case from the receiver, and used a VERY SMALL POINTED METAL PICK to clean the internal threads of the receiver ; and used a sharp high-carbon metal blade to provide the now-missing BEVEL to the normal Entrance for the Receiver Threads ! The first (normal) entry of the Case from the outside was a "little" weird , but after that first passage , it was easily accomplished with only finger pressure - almost like factory new ! I considered myself LUCKY ; but I'm sure anyone using the same process - AND USING A LOT OF CAUTION - AND GOOD JUDGMENT - could also repair a mildly damaged 550-1 receiver : worst cases would require a REAL gun-smith to correct and repair/replace damages !