Another of my long posts on OCD barrel prep and care:
Have one of the ARP 3R 20" 22 Nosler barrels and its screams top of velocity numbers for that tube length. Fire lapped as part of first couple of range sessions and my thin skinned bullets at stoopid velocity were loving that tube.Do not recommend this for most unless research subject well or you will ruin a barrel. Copper foul a barrel and keep shooting is a good way to cause damage. I never use the full kit and seldom if ever use all five grits. Based of my initial chamber cast and bore scope exam before barrel is ever mounted generally have an idea if its going to need fire lapping. Some I hand lap, some I fire lap, some both and others have my precision barrel guy lap. Some vendors lap barrels before ship and others offer lapping as a option. My chamber cast tells me if chamber may need polishing, is to slick (yes a chamber can be too smooth) or has a possible issue in neck/throat area..
With my bore scopes examine every inch of bore from end of chamber, the free bore area in front of rifling and on to muzzle. Use both a Lyman 22" digital and NGT150HW 26" bore scope as each has features I like.Having two allows me to keep one at work and home or carry to the range. Won't say one is better than the other but will say each does certain things differently but looking at a throat and bore using 3x magnification with pure white LED illumination will find tool marks, burrs and open pores in the steel. If those areas are not properly handled they will become copper grabbing nightmares that can ruin a barrels potential before its broken in. Buy barrels from three companies (stainless single point cut rifled air gauged...) that meticulously hand lap, inspect, lap, inspect till you get as perfect a bore as possible but that comes at a cost.
Take chamber casts of overbore hot-rod turn bolts every 500 rounds. A Lazzeroni Scramjet (0.257" bullet at 4,000+ fps) or 22 CHeetah (0.224" bullet at 4,000+ fps) has a pore begin to open in throat area with natural erosion, do not catch issue soon and treat, it can reduce the life of a 1,200 to 2,000 round barrel to 600 to 800 rounds. Have learned that the expensive way. Used to be a company called BlackStar that did microscopic "abrasion" treatment of barrels that cleaned them up sick as glass but not so slick you had a entirely different set of issues. Would send my barrels after chambering and profiling to BlackStar then have them cryogenic treated before mated to an action. Still a regular check with a bore scope after each cleaning and the 500 round (some barrels every 1,000 or 2,000 rounds) which compare to original tells you a lot.
Now video each barrel inspection and file in that rifles folder on my "gun computer" plus take still shots of areas and track wear visually along with gauges. Smooth over the tool marks, remove any burrs, close open pores or at least smooth that area and your starting with a barrel that can shoot to its real potential. Its one of the reasons my 18" ARP 5R 6.8 barrel is a first round cold bore coyote killer out to 450 yards. First its just a good barrel but it got treated like many would prep a $800 to $1,200 tube as once you learn a few tricks its fairly easy and cheap to properly prep a bore before it even starts break in then the tracking identifies any wear related issues that my begin to show and get that extra 400 or more rounds out of a very high strung cartridge or make a $250 to $300 barrel shoot better than most "barrel snobs" would expect. H has always provided good foundations but if prepped they want to act like barrels at twice the price point.
About Tubb Fire Lapping Kits:
The Tubb Final Finish Bore Polishing System is composed of a series of 50 bullets that are impregnated with 5 different progressively finer compounds. Enhances accuracy by polishing out bore imperfections. The smoother bore results in reduced fouling and less drag. Also makes the barrel much easier to clean. Removes no more than .0003" of metal from the bore and includes a reusable plastic case. This is not loaded ammunition. Reduced loads must be used when loading Final Finish Bullets. Bullets are made by Sierra. The grain weight of the bullets will be listed on the end of the package. Tubb recommends using the starting load listed in the Sierra reloading manual for that grain weight and bullet. Tubb also recommends not to go above the starting load for any reason.
Have never used all 500 bullets in all grits on a single barrel. Can usually prep four to five barrels out of a kit or say three then have enough left to "repair" flaws that appear with wear on a half dozen or more issues. Overdone or improperly done will ruin a barrel fire lapping before its broken in but based on every bore usually include fire lapping into intial break in and by the time those magic first 100 to 150 rounds are down the bore know have done all I can to give it its best chance to perform. The initial inspection will often show an issue that has to be addressed using a throating tool or some hand lapping before it gets even one round down the pipe. Yes I am OCD, ADD and lots of other malfunctions in one big bag of skin.
Same for torque, can buy a Ruger Mini 14, 10/22 or other firearms, shoot them our of the box or as acquired used and get a good idea of accuracy of the rifle using some very select test ammunition have found to be consistent for measuring potential of accuracy across a wide range of calibers in almost five decades of thinking like an engineer and a mechanic. Can disassemble a Mini 14 or 10/22, reassemble using torque wrench to properly torque all the screws in a Mini's gas block, screws that mate action to stock and others swapping zero parts to pick up 1/2 to 1 MOA, lap the bore and find some more and suddenly its not shooting like a Mini 14 or Walmart 10/22. (as an aside you can convert a Mini 14 trigger to binary and back with a staple or small piece of stiff wire)
Have the best luck making ARP barrels out shoot their MSRP of any tube out there. Can buy better to much better out of the box but comes with a MSRP to match its ability. Oddly have bought 80% of my ARP barrels from discussion groups and other internet secondary sellers. Buy mix of lightly used to purchased new but never built. Have a 16" (least favorite length) ARP 6.8 barrel that carries a night vision scope (even in 5.56 and 308 most of my N.V. is on 16" barrels) that before it got the 4x Gen 2+ CGT Starlight parked was shooting 5/8" in the testing and break in with my normal test scope (old early year 8-24x Horus Raptor) and had some honest 1/2" five shot from the mag groups as testing and break in ended. Have a 16" 5.56 White Oak Armament build with a 6x Gen 2+ WPT and a 16" AR 10 in 308 with a 6x Gen 2+ WPT (Gen 2+ WPT tested well as many Gen 3s and was best of the Gen 2+ IMO) staged out of the vault along with a Day/Night and Thermals.
A chamber cast, bore scope inspection, run trigger across Hammer & Sear Jig using test fit plate, square upper, torque wrench pass, treat bore based on inspection and have taken $399 Smith & Wesson M&P 15s people would swear is a $1,000 or more price point rifle. Sometimes wonder if some guns are assembled sloppily to encourage buyers to spend money on upgrade parts. How many buy a Ruger BX-25 trigger for their 10'22 when ten minutes with a Hammer & Sear jig plus $15 in springs will result in better trigger than a BX? Some days wish I were a gun smith and could help folks out but it would be hard to make a living charging 90 minutes labor and $20 in parts to get a happy stick. Of course many would want more than correcting factory sloppiness. Know one smith that does this, goes through factory turn bolts, installs one part makes himself but takes it apart, squares and fits every part, reassembles and returns your factory rifle with factory parts and it is truly a full custom rifle.
