Competitive 504 Remington

As a staff writer for Precision Shooting Magazine, I had authored an article on the Model 504 Remington .22 caliber target rifle in their September 2006 issue where I concentrated on the merits of precision bedding this rifle. Following in December 2006 I wrote an article for American Gunsmith on rebarreling the 504. The outcome of these works generated a good deal of response.

A devoted rimfire shooter in California urged me to build a Model 504 rifle for his special needs with expectation that I could replicate the fine performance I had demonstrated in my previous editorial coverage. Based on the inherent qualities of the Model 504 this was accomplished, resulting in two very pleased individuals.

Remington Model 504 Synopsis Remington produced the Model 504 rimfire in different models: 504-T heavy barrel varmint rifle in .22 Long Rifle and .17 Hornady Magnum Rifle, and the 504 Sporter in .17 Mach 2, and .22LR. It was also offered in a pricey custom grade in .22 LR. Here I shall expand on the rifle’s makeup and function and things I did as a rifleman/gunsmith in wringing out the utmost performance of this rifle. The Model 504 Remington was manufactured from 2004-2007.

A very heavy walled, one-piece cylindrical action is two-point bedded into a bottom cutout for a six-shot magazine that fits flush with the bottom of the stock. The round bolt is manipulated in normal fashion for cartridge feed, extraction, and ejection. The bolt is fully closed by means of a square lug at the rear of the bolt handle and at the rear of the receiver ring. A sort of dual locking lug enters a shallow mortice at the left receiver wall.

Two of the three models 504 have a cocking indicator at the rear bolt shroud center. The bolt is released by means of a button located at the left side of the receiver and is easily withdrawn. Cartridges are pushed forward by the lower margin of the front of the bolt and grasped by dual springloaded extractors on full closure of the bolt. As I shoot for ultimate precision, I don’t always use the magazine. Any soft-tip bullet deformation is avoided in this way and it has proved to be a good move.

The adjustable safety is located at the right side of the receiver— forward to fire and safe to the rear. The Leupold 3-10X scope is mounted with Redfield Jr. rings and base. The Model 504 Remington becomes a convenient switch-barrel rifle capable of extreme accuracy.

The Allen-head bolt is shown at the bottom of the receiver used to solidly clamp the receiver to the barrel. They form a solid and precision fit when locked together. I will cover this in more detail as I discuss trigger function. The rifle is drilled and tapped at the top of the receiver ring for standard scope mounting using a variety of base and ring styles. Barrel Removal and Changing Those whom have read much of my writing know I am very devoted to the switch-barrel rifle.

This includes a number of rimfires now inclusive of the Remington Model 504. The shank of the 504 barrel is turned down to 0.673" diameter and 0.896" in length. This fits into the receiver, allowing the axial face of the barrel to mate with the receiver. A hardened, 10/32" Allen head angularly positioned screw tightens the split receiver to the barrel. When fitting the 504 barrels I machine the barrel shank about 0.002" larger than the 0.671" factory diameter for a better fit.

This eliminates some of the draw-down pressure required of the rather small screw which is torqued to about 45 inch-pounds. In the chambering and headspacing process the two extractor slots are formed exactly like the factory barrel. There also is an alignment slot that aligns barrel rotation, matching a pin within the barrel channel. Moderate hand pressure is applied to the receiver as torque is applied to the barrel lock screw.

A good test for barrel shank lock up and precision involves shooting a group, followed by barrel removal and replacement, and another group to test for both accuracy and group placement repeatability. The Remington 504 rifles I have worked with all passed this test. As a perfect example of this test, I was demonstrating a Model 504 Remington equipped with a Broughton 1:17 twist barrel using Lapua Midas bullets at 50 yards. Five-shot groups were consistently within 0.166" and 0.235".

The barrel was removed and replaced with essentially no measurable changes in accuracy or point of impact. Sure does wonders in promoting a rifle and its ammunition. Far In the rearward position the safety totally locks trigger movement.

Trigger is locked solidly to receiver with two screws front and rear. 25 pounds on the Model 504 Remington rifle. Though fully adjustable, Remington recommends factory adjustment of this trigger by a competent gunsmith. While on the barrel I will give some attention to the chamber. The original factory barrels on all three rifles were replaced with premium target weight barrels. The two that remained in my test rifle inventory were replaced with Broughton and Green Mountain 1-17 twist barrels.

I chose Dave Manson Precision Reamers (MansonReamers.com, to form the chambers. It was apparent that the Bentz chamber allowed chambering and extraction of most unfired rounds more easily than chambers cut with the .22 match chamber. Chamber length difference was 0.150" in these two chambers. Lead bullet tip land engagement accounts for most of this difference. I did install a bit stronger extractor spring on both bolts to aid in better extraction.

I have often gone to great lengths in improving rifle accuracy, and installation of match grade barrels has invariably improved factory rifle accuracy, including the rimfire rifles. The original factory barrels were retained for future use, if desired, interchangeable on each rifle. Bedding I’ve always regarded the barrel, the bedding, and the bullet as the keys to best accuracy in a rifle and the Model 504 was no exception.

On close inspection of my first 504 Remington Target stock there was a two-point bedding system. I saw where there could be some major changes here to good advantage. As the illustration will show, I installed three milled brass pillars on the 504 wood stock. The forward Some of the tests resulted in noticeably improved accuracy. The rear pillar was added by the author to draw down the tang to the added brass pillar. one is positioned at the front of the receiver ring directly beneath a through screw hole.

The central recoil lug is a short, internallythreaded bolt attached directly to the bottom of the receiver. This allows a short bolt to draw the action down into the stock. This actually serves as the primary recoil lug. I then added a third pillar on the flat surface of the rear tang just behind the trigger housing. Here I drilled and tapped a screw hole in the tang for a 1.540" length 10-32 screw. This served as the final link in a most precise three-point bedding system.

The barrel used was a 1-in-17 twist Broughton, along with ammo by Lapua Midas+ and Wolf Match Extra. This barrel was chambered with a Bentz reamer by Dave Manson Precision Reamers. All-Important Trigger The benefits of a quality trigger in delivering best accuracy in a rifle cannot be over emphasized. Benchrest performance is in no small way augmented by a really good trigger.

In my overall evaluation of the Model 504 Remington Target rifle, the trigger immedi- Top rifle has a well finished Sporter walnut stock and Sightron 3 1/2-10X scope. Quality checkering adorns this stock. Bottom rifle is the Remington Target version with laminated stock. This rifle wears a 3-12X Leupold scope. Both have one-piece bases with cut-out at the loading port. Barrels below are original issue in standard and target weight.

As switch-barrel rifles they are top quality, superbly accurate arms. ately caught my attention. As the pictures show, the 504 trigger is very compact and neat looking in appearance. It has a square sear to mate with the square bolt cocking piece. Two screws attach the trigger body to the action located at each bottom end of the trigger. The trigger has a safety lever attached at the right side, extending well upward—forward to fire and rearward for safe. The safety is adjustable for engagement.

While the trigger is adjustable for sear engagement, pull weight, and over-travel, Remington strongly suggests such adjustments be performed by an authorized Remington repair center. The triggers on the three Models 504 that I worked with arrived with about a 3.5-4.5 pound pull. I’ll not discuss this further here save to say this is a most excellent adjustable trigger which should only be worked on by a competent gunsmith. Be that as it may, the trigger can be safely adjusted for precision target work.

As sighting equipment, I used the Redfield Jr. mounting system which kept the rather short loading port open with the recessed base. Redfield medium height, horizontal, split rings provided a solid, fully-adjustable mounting system. Scope choices included Sightron and Leupold with fine reticles and adjustable objective lens. At 10X I could easily see well enough to bisect a bullet hole. Rimfire recoil is less likely to upset scope stability as some of the high power rifles do and scopes remained solidly sighted-in.

Those Remington Model 504s that I worked with all get a very solid recommendation. With a few changes they will shoot with the best of them. AG