August 2001

Fire-Lapping: Is NECO’s Bore Treatment Kit Worth The Trouble?

We’ve read about fire-lapping for years, and some of us had dabbled in this black gunny art with home remedies. But until now we hadn’t tried one of these products. We liked it.

The NECO fire-lapping kit included lead slugs
ûfor checking barrel smoothness and several
ûgrits, which were embedded in the bullets by
ûforcing the abrasive into the jackets.

Fire-lapping, a mechanical process designed to clean up rifles bores so they will shoot better and be easier to clean, has long intrigued us. If such products could indeed deliver generally better bore condition, then they would likely be worth the money and effort.

We decided to test one such product made by NECO, (707) 747-0897, short for Nostalgia Enterprises Co. Specifically, we got the “Pressure (Fire) Lapping Kit” from Brownells, (641) 623-4000. Although the kit is available with lead slugs in .22, 6mm and .30 caliber, it can be used on any rifle or handgun, and is supposed to be very effective in muzzleloaders. We specified .30 caliber (catalog number 643-100-308, $66.50), because we had on hand three troublesome rifles that needed to be dealt with.

The rifles were a Savage 99 in .300 Savage, a pre-’64 Winchester Model 70 in .30-’06, and a heavy-barrel .308 custom rifle on another pre-’64 Model 70 action. The troubles with each rifle ranged from poor accuracy to difficulties in cleaning. We’ll go into each rifle in more detail later, but first we must say the rifles were more than worthy of barrel resurrection based on their external appearances and overall qualities.

When the NECO kit from Brownells arrived, we looked for the .30 caliber bullets. There were none. Instead the box held a package of .30-caliber lead slugs, the purpose of which at first escaped us. We eagerly opened the instruction manual and started to read. That’s when the first — and only — disappointment of the NECO package hit us. The instruction manual was very poorly written and poorly organized. It desperately needed the services of a good editor. The information is all there, but none of it is readily available at a glance, and there is, in some cases, far too much information, some of it non-essential to the task.

Within the kit were four plastic vials of abrasives, labeled 220, 400, 800, and 1200 grit. Also there were two pieces of steel. One was a short plate an inch wide and 6 inches long. The other was half an inch square, and 3 inches long. These were to be used to embed the varying grits of fire-lapping material into the bullets that the user had to provide.

Per the instructions, it was essential to begin by cleaning the rifle bore as well as possible, using something like J-B Bore Cleaning Compound, and to clean and check the progress of the job after every five shots with the fire-lapping loads. We got thoroughly sick and tired of cleaning rifles long before we were done with the three rifles.

Next was the task of preparing the bullets. We guessed, from the data in the instruction manual, how many bullets of each grit we’d need for all three rifles, and prepared these in advance. It was necessary to keep the varying grits of prepared bullets separated physically, to avoid confusion. They all looked alike. The instructions stated that jacketed or lead bullets could be used. We used Hornady and Speer jacketed soft-nose bullets of 150- and 165-grain weights. We first prepared the finest-grit bullets, which would be shot last, and moved through each coarser grit, preparing the 1200-grit final-polishing bullets last. The technique was to anoint the larger steel plate with some of the abrasive paste, and then roll a bullet between the two steel plates, using heavy finger pressure to force the grit into the surface of the bullet jacket. With a little practice it was easy to tell when the bullet was suitably impregnated. The bullets don’t hold much, but it was enough to get the job done. Per the instructions, we prepared bullets with the finest grit first, to avoid cross-contaminating finer-grit bullets with left-over coarse grit on the steel plates.

The bullets were then wiped gently, and, beginning with the coarsest grit, loaded over light charges of powder (the instruction manual gives suitable loads for a great many cartridges), and shot through the rifle. The instruction manual gave suitable light loads for a variety of cartridges. We used small charges of Alliant’s Unique powder throughout, with no filler.

The lead slugs were used to gauge the progress of the job. Initially, with the bore as clean as possible, and before firing any bore-lapping bullets, the bore was oiled and a lead slug was then pushed through it. A bit of experience at this task gave the shooter a feel for how bad the bore was initially, and how well the fire-lapping task was progressing. As fire-lapping continued, the lead slug moved progressively easier and more smoothly through the bore. All three bores ended up with a miniscule taper from the breech to the muzzle, which was easily felt as the lead slug was pushed through the barrel.

The 220-grit did some fairly significant metal removal. This grit was recommended only if a bore was rough, pitted, or in serious need of smoothing. When we used this grit on the rifle with the worst bore, the .300 Savage, we were surprised how quickly that barrel smoothed up.

Prior to our fire-lapping, we shot each rifle for group and also evaluated each one for ease of cleaning and for the physical appearance of the bore. Here’s what we found with each rifle.

Savage Model 99, .300 Savage
This rifle had been made in 1924. Over the years it had seen much use, but when it came to us it had been very lovingly reblued. We don’t know who the artist was who did the metal preparation and polishing, but he did a job worthy of the very highest-grade firearms existent. The quality of surface finish and flatness, retention of all markings and sharp corners, polish marks all running the same direction, avoidance of dishing or uneven polishing, would have made James Purdey himself proud.

Unfortunately, pushing a patch through the bore was a chore. The patch would usually tear. The bore was dark looking. There were some very minor pits, but all the rifling was sharply defined. With the rest of the rifle looking like a million bucks, it was a pity the bore was so bad. Hence the call for fire-lapping. We hoped it would at least smooth the bore, if not improve the rifle’s very mediocre accuracy. We shot pre-fire-lap groups on the order of 6 inches at 100 yards, using the fine old pop-up aperture rear sight and a solid machine rest.

The first lead slug through the barrel confirmed our doubts about the bore’s condition. The lead slug didn’t want to move, and we had to use significant force to get it through, even though we had oiled the bore well per the instructions. Then we started shooting the abrasive-loaded bullets.

After five shots with 220 grit we cleaned and oiled the barrel, and pushed another lead slug through it. With the lever-action Savage it was necessary to slug it from the front, which was not as informative as doing it from the rear, but we could indeed tell progress. There was a sticky portion just behind the muzzle, then the slug fell nearly free until it again encountered strong resistance over the last foot of barrel. We had our work cut out, and continued shooting and cleaning and testing until we had fired 20 rounds of the coarsest-grit bullets. At this point the bullet felt completely uniform all the way through the bore, though it was tightest at the muzzle. We proceeded to shoot ten each of the next three grits, to polish and complete the job. We tested with a lead slug occasionally, and always cleaned the bore after every five shots. We could feel progress on the cleaning patch all throughout the process, which in all, took fifty fire-lapping shots.

Finally we tested the rifle again from the bench, using our full-power handloads. We had six loads remaining of the batch we had used prior to fire-lapping. Imagine our disappointment as the first four made a large rectangle on the target. Sadly we fired the last two shots of our handloads, and they were touching, right in the center of the rectangle. Aha, we thought, we were just putting the final touches to the job, and maybe blowing out the last of the grit from some pores we couldn’t clean. We eagerly loaded up more rounds and took ‘em to the bench. To our joy, this rifle put all shots well inside 2 inches at 100 yards. Also, the bore is very much easier to clean. With this fine old Savage, fire-lapping was well worth the effort. Now the bore and the shooting qualities match the appearance of the outside of this grand old rifle. Score one for NECO.

Pre-’64 Model 70, .30-’06
This old rifle was in excellent original condition, and had a factory-installed Lyman Model 48 aperture sight. Accuracy had been plenty good enough, but we had felt some roughness in the bore that we didn’t like, and it was rather difficult to get the bore entirely clean. We hoped to get easier cleaning, smooth up the roughness, and would gladly take any accuracy benefits we could get, if they came along.

The pre-’64 Winchester Model 70 had a rough
ûbore and was difficult to clean. Fire-lapping

We first thought we could bypass the coarsest grit, following the recommendations of the NECO instruction manual for moderately good barrels. The first five shots with 400-grit bullets didn’t do much, so we put five 220-grit slugs down the barrel. This got us off to a good start, and as we progressed through the varying grits we could feel a distinct ease in the cleaning effort. Each time we tried a lead slug to monitor our progress, it went ever more smoothly through the bore. When we were done shooting the 1200-grit bullets, we shoved a final lead test slug through the bore. It moved very smoothly and with low resistance until it got near the muzzle, where we felt a gradual and gentle increase in pressure.

When we tried the rifle on the bench with Winchester Match ammunition, we got poor accuracy for the first four shots. In fact we got a significant vertical string, indicating a possible loose action screw. We checked, and found everything okay. Recalling our experiences with the Savage, we kept on shooting, and after a few more rounds, our accuracy returned to the same, or slightly better, condition it was in before we began. The big benefit here was in the great ease of cleaning this rifle’s barrel, and the apparent extreme smoothness of the bore after our fire-lapping was completed. Score two for NECO.

.308 Heavy-Barrel Custom Rifle
This heavyweight had a 28-inch barrel that felt fairly smooth and shot like a house-afire. Only problem was, the bore had to be cleaned after about every ten shots to give its best performance. Also, the rifle would not shoot its best until the bore had been fouled with a shot or two. Neither of these conditions are at all unusual for very-high-performance rifles such as this. This particular .308 regularly puts all its shots inside half an inch at 100 yards. But we thought we’d like to see how much of an improvement we could make, if any, by fire-lapping.

We began with the 800 grit, not seeing much need to rough up an already great performer with any coarser grit than absolutely needed. After ten rounds of that grit and 20 more with 1200 grit, we tried the rifle again on the bench with our same sample of match ammo. We found the first shot from a squeaky-clean barrel landed closer to the subsequent shots than ever before. We fired 20 shots without cleaning the bore, and got outstanding accuracy all along. Best of all, the rifle barrel is now much easier to clean. Score three for NECO.

Gun Tests Recommends
Pressure (Fire) Lapping Kit (Brownells catalog number 643-100-308), $66.50. Buy It. We recommend the NECO fire-lapping product without hesitation.

We conclude that fire-lapping offered significant benefits to all three rifles. Although the task was not much fun, what with all the reloading, cleaning and checking, it proved to be worth the effort in all cases. Users without a private rifle range would most likely make many trips to the range, or would need to pack along loading and cleaning gear. However, fire-lapping seemed to offer benefits that outweighed the minor troubles and fussing associated with the procedure. With an 8x loupe we could easily see the metal of each bore becoming more and more polished as each lap job progressed. Also, once a barrel is lapped, it’s done. You’ll get the benefits of fire-lapping throughout the life of the rifle. There’s no need to go back every few months to renew the job, assuming normal care.

When our three rifles were done, we still had most of the abrasive compound left over. There appears to be enough grit to do dozens of rifles. We conclude this process is well worth the effort, though we’re not sure you need to run all those lead pills through the bore along the way. We found we could tell a lot from the feel of the cleaning patches, but we still used the lead slugs to double-check what we thought we were feeling. We suspect we’ll be lapping plenty of other bores in handguns, black-powder firearms, and rifles during the coming months.