|
Post by wheelguns on Feb 24, 2019 13:12:22 GMT -5
When I said “hot” loads,I didn’t mean overpressure loads. I should have been more clear. They were just hotter than I normally shoot in these guns. It has been quite some time since I did this. If memory is correct, I shot 9gns of unique with a 250gn xtp in my blackhawk, and in the uberti, I shot the same bullet with 8gns. I realize these aren’t hot loads by anyones standards, but it worked for me, and both guns shoot great to this day with no leading what so ever.
I tried everything to stop the leading. I tried a bunch of different loads. I tried softer bullets. I tried harder bullets. At the time, I had never heard of thread choke. While doing exhaustive research, I came across the term thread choke on the LASC website. I read Glenn Fryxell’s articles, and what he described was exactly what was happening to my gun. I bought bear tooth bullets technical guide, and was going to firelap this gun. The problem was that at the time all of my shooting was at an indoor range with little benches. I couldn’t figure out how I was going to do this up there. I had bought the blackhawk when I first started reloading, and wanted to shoot cast bullets. I couldn’t afford to shoot jacketed bullets. This worked for me. Maybe My thread choke wasn’t too bad, but after 50 rds of cast bullets, before I did this, I had a big mess.
|
|
|
Post by bradshaw on Feb 24, 2019 13:14:20 GMT -5
Bradshaw: What i dis was start a slug about 3cm down the barrel and then use pieces of said wood dowel to push it back out through the muzzle by inserting them through the window frame, i then pushed a slug al the way through the barrel and the difference was 0.06mm. The felt resistance begun about 5mm inside the frame or in the middle of the threaded part of the frame. I would agree that using a set of pin gauges would be the best but it is a long time since we used inches over here so finding a set is long shot, i have looked in to buying one but with shipping that would cost somewhere around 400$ so that will have t wait Perhaps it is best i share some history of this gun. I bought it new 2001, it will shoot jacketed bullets reasonable well, 6cmm at 25m both 38spl and 357mag. It has not done well with cast shooting large and irregular. So why have i not done something about this before now ? Well as i said i shoots well enough for what i use it fore, we call it field shooting, a competition form were you shoot at different size targets on time and you only count hits not group size, and jacketed bullets has not been that expensive. during the years i Wold say that i have put some 9000 38 spl and 2000 357mag through her. Now prices are starting to go up and i have had nothing but success with lead bullets in my Ruger Bisley 45 Colt, and my Kimber 1911, 45acp and them i use for bullseye shooting so i thought i would give this a try again and at least se what the problem is and see if i can do something about it Best regards Mathias ***** Mathias.... thanks for background on revolver and your shooting. Given 9,000 Specials and 2,000 mags fired through your M-586, I would firelap. I might experiment with fine diamond abrasive on jacketed bullets as well as the standard lead bullet for lapping. A jacketed bullet must be pushed harder to exit the bore. I would not load a jacketed bullet marginally light, as a SQUIB LOAD will be much more difficult to drive through the bore, especially since it would have to be driven from muzzle to breech and pass over the constriction ring. I would use .357 mag cases for all fire lapping with lead or jacketed. I would DEEP SEAT the bullets in FIRED cases, with a barely perceptible flare at the case mouth to receive bullet impregnated with lapping compound. .357 Mag case* Lead bullet----deep seat bullet over minimum .38 Special charge of fast powder. If necessary, crimp absolute minimum to chamber round or to hold bullet from slipping. * Jacketed bullet----deep seat bullet over full .38 Special charge of fast powder. If necessary, crimp absolute minimum to chamber round or to hold bullet from slipping. Instead of measuring with gauges, note progress by slugging bore for smoothness all the way through. Check progress at the target, also. Keep and annotate targets. The whole may be spread out over time. I would not rush to complete the work in one day. David Bradshaw
|
|
jgt
.327 Meteor
Enter your message here...
Posts: 781
|
Post by jgt on Feb 25, 2019 8:56:53 GMT -5
The very first thing I would do is check my cylinder throats. Make sure they are all correct and the same size from each cylinder to the next. When they are good to go, I would shoot a "before group". Then I would purchase the Beartooth Bullets Technical booklet. Once I understood the process, I would purchase the wheeler fire lapping kit with four different grits. Start with soft lead bullets coated with the course grit rolled into the bullets between two steel bars. Work from course to fine grit. Shoot ten rounds or so then stop, clean the gun, and slug the barrel. Shoot some more lapping bullet. Stop, clean, and slug the barrel. If you shoot the lapping bullets at a target, you should be able to see the groups shrink. If it is a stainless gun, it will take more lapping. Some stainless guns take up to fifty rounds of 400 grit to remove the restricting area. When the restriction gets close to being removed, you start moving to 600, then 800, and 1000 grit compounds. Read the booklet, they don't mention using the other grits if I recall correctly, but I would encourage you to use the increasingly finer grits until the desired diameter is reached. When I was satisfied with the firelapping I would have the crown and forcing cone checked. If they are good then there is nothing more to do but shoot the gun. An "after group" would now be appropriate. There is really no "chiseled in stone" method. This is how I would do it. Good luck.
|
|
|
Post by mathias on Feb 25, 2019 11:43:22 GMT -5
Looks like i will try my hand at fire lapping then I will order me a copy of Beartooth Bullets Technical booklet and do some reading first. About my cylinder throats… they can be my next problem, i measured them when i first got the gun so it is some time ago but my notes tells me i have 3 that are 9,07mm (.3573") and 3 that are 9.08mm (.3577") and i have sized my cast bullets using a .358 die and a lyman 450 lubreicer. Measurements of my barrel during this constrictions problems indicates that my barrel is 8.95mm (.3526") Is that not a tad small for a 38/357 ? And should i size my cast .357 instead of .358 ? Thanks for al help and patience Mathias
|
|
|
Post by bradshaw on Feb 25, 2019 17:57:49 GMT -5
Looks like i will try my hand at fire lapping then I will order me a copy of Beartooth Bullets Technical booklet and do some reading first. About my cylinder throats… they can be my next problem, i measured them when i first got the gun so it is some time ago but my notes tells me i have 3 that are 9,07mm (.3573") and 3 that are 9.08mm (.3577") and i have sized my cast bullets using a .358 die and a lyman 450 lubreicer. Measurements of my barrel during this constrictions problems indicates that my barrel is 8.95mm (.3526") Is that not a tad small for a 38/357 ? And should i size my cast .357 instead of .358 ? Thanks for al help and patience Mathias ***** Mathias.... do not touch the CHAMBERS. Target now and at stages of fire lapping. Form chamber exits hold the heel of bullet straight as its shoulder enters the rifling. My rule for dealing with accuracy is to work one detail at a time, then TARGET. David Bradshaw
|
|
|
Post by mathias on Feb 26, 2019 11:28:07 GMT -5
I was not planing on doing anything to them i just thought they seem large compered with my barrel. I totally agree that you should only change one thing at the time. Found out that Beartooth do not ship/sell outside of the USA so that´s a bust
|
|
|
Post by bradshaw on Feb 26, 2019 12:12:32 GMT -5
I was not planing on doing anything to them i just thought they seem large compered with my barrel. I totally agree that you should only change one thing at the time. Found out that Beartooth do not ship/sell outside of the USA so that´s a bust ***** Mathias.... you’re probably 6 or 7 hours earlier than East Coast U.S., probably at dinner. Get whatever lead bullets you can at a friendly price. If hard cast is all you have available, roll with more pressure to imbed the lapping compound. If jacketed was all I could get, I’d figure a way to imbed the lapping compound. Be sure to have a stout brass rod, hammer, and oil to drive out any slug which sticks. No need to report my experiment to find a minimum charge that expels the bullet from the muzzle. I made a number of squibs in .45 Colt----a cartridge with huge EXPANSION RATIO----to learn that there is a zone of behavior at which some bullets exit and other SQUIB (stick in bore). I was able to stop lead .45 bullets in a 5 gallon pail of water----without puncturing the bottom----but not without squibs. Have all your tools and cleaning gear on hand when you firelap. Grease area between cylinder and yoke; clean and re-grease frequently. You do not want abrasive between cylinder & yoke. David Bradshaw
|
|
|
Post by mathias on Feb 26, 2019 15:53:52 GMT -5
Bradshaw... I have some bullets i cast using 50/50 ww/pb that i can use for this. And i have from pure lead and up to linotype if there is some advantage using a harder or softer bullet. I just placed a order for a wheeler bore lapping kit, i guess it will take a weak or to get here. But if i have understod the process right i will start by shooting a group for reference, then lapping by using a minimal charge in 357 cases fired in the gun (not calibrated just flared) fire 6 rounds, clean and check if i still can feel the ring. I would need to go to the range to be able to shoot a group, but i can shoot the lapping rounds in my backyard just not at a target, it would be easier just going in an clean and measure and continue the process. But others have said to watch how the groups prints on paper so i will not do so if it means i will miss something important Regards Mathias
|
|
|
Post by warhawk on Feb 26, 2019 16:10:05 GMT -5
Somehow I posted to the wrong thread.
|
|
|
Post by mathias on Apr 16, 2019 10:05:18 GMT -5
Hi As the snow slowly melts away and once again reveals the range i have finally been able too try and see if my fire lapping done something good. I think i have made the barrel more even than it was before. My measurements has been done by driving a slightly flattened cal 36 round ball through a well cleaned lightly oiled barrel. A measurement of the muzzle was done by driving the slug back out with pieces of a wood dowel, several slugs was measured and this is what i got Muzzle end 8.93mm Rear end 8,94mm This would mean that my barrel is about .352 is that not a bit small for a 357mag ? And here are the results of my test shooting: 10 rounds were fired of each loading, gun cleaned in between. I was shooting sitting on the ground, my back supported by my car, revolver between my knees, so there are some play built in there but it was the best i could do for now. There are 25mm between the lines and i have marked out the rounds that landed outside the removable target. So is there some suggestions on what (if anything) i should do now ? I can add that the group shot with lead ist the best lead group i have had with this revolver
|
|
|
Post by bradshaw on Apr 16, 2019 11:31:25 GMT -5
Mathias.... need more info on targets * DISTANCE. * Powder and charge. * COL (Cartridge Overall Length), especially for cast bullet. If you use a light charge of fast powder in .357 Mag brass, I would DEEP SEAT bullet, with front band .040-inch (1.01mm) below case mouth.
Lead bullet When fire lapping, I would deep seat. Since case mouth is belled slightly to seat bullet impregnated with lapping compound, ROLL CRIMP just enough to chamber round. A belled mouth probably won’t chamber. There is no need to roll crimp fire lap ammo, and it may brush off lapping compound before bullet enters barrel.
Jacketed bullet In your situation with limited availability of components, I might very well commence to firelap with jacketed bullet rolled between steel plates with lapping compound. A jacketed bullet might----might----lap the bore faster than a lead bullet. Note that rifles are firelapped with jacketed bullets. A difference with the revolver is found in the CYLINDER/BARREL GAP: a jacketed bullet requires more pressure to exit the muzzle, sow th lightest practical load with a lead bullet may stick the jacketed bullet. More force is required to drive stuck jacketed bullet.
Groove diameter .352-inch (8.94mm) is small for a .357 bullet. Nevertheless, Colt Python ace Jerry Moran has measured Python grooves of .354”, and probably less, from accurate Pythons. Colt Pythons have a reputation for tight bores & grooves, including rifling which tapered down from tenon to muzzle. However, I’ve never seen the nature of this taper articulated. A Python with “tapered barrel”----the BORE was reamed to to taper with a straight reamer. GROOVES are broached and do not taper. The practice ended when the man running the reamed departed Colt. Pythons made later do not have a tapered bore. David Bradshaw
|
|
|
Post by mathias on Apr 16, 2019 12:42:32 GMT -5
Bradshaw: Distance to target was 25m Jacketed load is 6,5 grains vithavouri N32C, 158 Grains jfp V0 300 m/s (chronografed) Col 36,5mm 38spl cases
The lead bullet is a IDEAL 241477 150 grains 5 grains N32C i just took a load in the middle of what the handbook suggested for about V0 300 M/s Col 37,8mm. Sized 38 and gives a slight resistance when pushed through the cylinder throats. The same bullets was used in fire lapping but using 357mag cases belled just so they would chamber, 2gr vv N310, finger seated the bullet flush no crimp needed Fired 12 rounds coarse, 18 dr medium and 24 fine so far
N32C is also known as Tinstar and is a bulky powder and gives a good fill out in cartridges originally made for black powder /Mathias
|
|
|
Post by matt56 on Apr 16, 2019 16:13:38 GMT -5
Not sure if it's been mentioned or not but a S&W revolver barrel has an odd number of lands and grooves. You cannot just stick a caliper on a slug driven through the barrel and get an accurate measurement. If you had an even number of grooves you would have a grooves 180° apart and could accurately measure bore diameter. Sorry but I do not know how to measure groove diameter on a S&W revolver.
What I do know about now though is a range rod. With seven different 686s lined up to measure I found that 3 have thread choke and one has a bore so tight that the match rod will not even enter the barrel. These are all different years too, from no dash to dash 6.
|
|
|
Post by bradshaw on Apr 16, 2019 19:08:01 GMT -5
Mathias..... 25 meters? It could be worse. To test your M-586, I would shoot it from a rest.... or Creedmoor: these positions provide the longest EYE RELIEF----distance from EYE to FRONT SIGHT. To assure my position and squeeze, I would dry fire 5 “shots” before live fire.
That you feel bore compression at the mid-point of barrel tenon in frame indicates more firelapping. You want to remove that constriction so the bullet doesn’t rattle down the barrel. You are on the right track. Keep shooting and report progress. David Bradshaw
|
|
|
Post by ezekiel38 on Apr 16, 2019 20:41:50 GMT -5
Glad to hear your "choke" is getting better!
|
|