New Barrel

[686]

i have a new 45-70 tc rifle 23 in. barrel comming. i know how to brake in a barrel when useing jacket bullets. i plan on using cast in this barrel. do i need to brake it in with jacket bullets or is there a way using cast? thanks charles

[felix]

Use jacket bullets. ... felix

[686]

thanks flex. that was my thought. looking to buy a magma mold for my magma caster. they have a 300 gr rnfpgc w/2 lube rings and a 340 gr rnfpgc. w/3 lube rings. for this tc 23 in barrel which would be better? thanks

[docone31]

I have pondered this many times. What is the best way to break in a barrel.
The machineing will be sharp, some feathers here and there.
I pondered, firing about 100rds jacketed, then firelapping. The throat will move forward a tad, but us caster/reloaders can adjust OAL. The throat transition would be smoother. Now, whether this would be a good thing, or not remains to be seen.
I have wondered the best way myself. I have in the past just fired to break in and I was pleased with the results.
I bet a lot of people will have opinions also.

[felix]

686, get the 340 because it is more appropriate for the case size and spirit of the caliber. The 405 would be the most appropriate, however. Let the the amount of lead required (recoil, fun, trajectory) be your guide. ... felix

[Boomer Mikey]

Go through the usual process of cleaning the new barrel real well and scrubbing it with JB to clean and polish the grooves and to remove any scale without significant dimensional changes, then slug the bore at the muzzle and chamber and run a slug through the full length of the bore to find out the barrel's characteristics (taper, roughness, constrictions). Then make an impact or poured chamber cast and compare what you have to the bore's measurements, SAAMI specifications, and your brass. With all that information you can determine if the barrel should be returned for a major defect or benefit from a conditioning process such as firelapping or hand lapping. I wouldn't firelap a barrel if it didn't need it.

All of this can save you a tremendous amount of guessing and praying to the cast boolit gods. You will know if the barrel is smooth, what the groove diameter is, if the barrel has a taper and which direction the taper is, if there are any constrictions or rough areas and approximately where they are.

Have a gunsmith fit the barrel to your frame; especially if your frame is a Contender to assure proper headspace and lockup. A bad fitting barrel can destroy the Contender's locking lug bolt table. All barrels that share the frame should be checked and fitted as necessary.

TC has a bad habit of shipping barrels with oversize bores and chambers that aren't aligned with the bore. Don't ask me how I know... They ship good barrels too but why torture yourself trying to get one to work if you can exchange or return a bad one for a good one.

Shooting jacketed bullets will improve an otherwise good new barrel's condition for shooting cast boolits by smoothing machining marks in the bore and throat in the process of normal wear. The usual break-in procedure of fire one clean, fire two clean... until you reach 100 rounds seals the pores in the metal and to some degree smooths the surface of the lands and throat. Jacketed loads won't remove constrictions or high spots and grooves don't get much attention as the bullets tend to ride on top of the lands and are too hard to obturate to groove diameter. Jacketed bullets will follow the contour of the barrel including constrictions and taper.

The same break-in procedure using oversize hardcast boolits will easily take twice as many rounds or more but will improve all surfaces including grooves.

If you want to speed the process up considerably you can (at your own discretion) embed some BHN 12-15 cast boolits with J-B bore paste with low velocity loads for minor bore conditions (more of a polishing).

As the severity of the bore's condition increases I use lapping compounds as recommended in both Marshall Stanton and Veral Smith's books using their firelapping procedures with low velocity loads to remove constrictions and very rough bore conditions. In many cases a significant improvement in bore condition can take place with as few as 10 - 20 rounds. I don't use these measures indiscriminately... only where it's indicated that these measures will improve the situation. Firelapping is an accelerated wear procedure that must be preformed as described in Veral Smith and Marshall Stanton's books. Done correctly, the process can improve some barrels to perform well... especially with cast boolits.

Sorry for the long post,

Boomer :Fire:

[686]

i was thinking of casting some stright liontype bullets in stead of jacket. did not think about jb past. i would want to take a 5 gal bucket fill it with sand to shoot in to so i could get my liontype back. thanks

[Boomer Mikey]

i was thinking of casting some stright liontype bullets in stead of jacket. did not think about jb past. i would want to take a 5 gal bucket fill it with sand to shoot in to so i could get my liontype back. thanks

Linotype isn't necessary, air cooled WW's are fine.

I made a 15 gallon bullet trap to recover my boolits in... 12'' diameter 1/2" thick steel pipe 36" long , 1/2" thick bottom and top plates with a 1" thick steel slug on the bottom welded to a 10" 3/8" pipe 12" long with a 1/2" thick piece of 3" angle on the bottom and a 1/4" thick 8" diameter 12" long pipe welded to the top; all filled with 18-20" of 30 mesh sand. It's mounted on wheels to move it around and I clean it out about once a year to recover the lead. No dents in anything; way overbuilt. I use thick rubber doormat material sitting on top of the sand to keep the sand from flying around and old cotton towels layered on top of the mat to keep the dust cloud to a minimum.

It's nice to be able to test loads for presure indications before loading a full range of test loads, function test guns, fireform cases, and do some barrel break-in/conditioning in the shop.

Boomer :Fire:

[686]

that type of teating and cron. testing, i just open the back door of my reloading room and shoot 90 yrds to my burm. i was meaning stright liontype instead of jacked. i would use the softer ww with jb. have you used a 23 in tc barrel in 45-70? what bullet weights and loads did it like?

[Boomer Mikey]

I own an H&R Shikari, a 22" NEF Handi", Marlin 1895 Cowboy, Browning 1885 Hi-wall, and a Winchester 1886.

I don't like boolits heavier than 360 grains in the light rifles with full power loads. The Hi-wall and 1886 are fine with 405 grain full power loads and I use 525 grain boolits only in the Hi-wall. I use H4198 & H4895 for reduced power loads; H322, H4198 and H4895 for full power loads. I don't care to use faster burning powders than H4198 but that's just me.

There's plenty of cast boolit load data available.

Full power 405 grain loads in a Contender wouldn't be my cup of tea.

Boomer :Fire:

[pdawg_shooter]

Paper patch the first 100 or so. It will give you a great polish.