243winxb
Member
The American Riflemen Reprint lists a Type 38 Training rifle as smoothbored.
Arisaka Model 38 6.5x50 - Bulge in cartridge
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rcmodel
Member in memoriam
Not all of them were smooth-bore.
They also used reject or worn out Type 38 barrels.
I have seen both kinds on GI bring-backs with the cast or welded receiver tang.
rc
They also used reject or worn out Type 38 barrels.
I have seen both kinds on GI bring-backs with the cast or welded receiver tang.
rc
Well I shot a new round that is a norma 156 gr softpoint. As you can see from the picture there is no bulge. Previously I trimmed to 1.974 and full length resized like i always do bringing the die down to the plate and then a slight 1/4 turn. Then seating bullet with coal of 2.80.This time I trimmed again to 1.974 but when full length resizing I took die to top of plate and back off just a bit. Then seated bullet but this time to 2.920 which is what the lee data sheet says is the minimum. I had been doing a coal of 2.800 per my rcbs book which if i believe the lee data sheet would make it below the minimum.
anyway after firing the reloaded cartridge as indicated above got a very very slight bulge hardly even a bulge and much much less than my previous reload.
Anybody got any ideas. I have added 3 pictures. one is the original cartridge before firing - the next is right after firing and the next is after being reloaded and fired. I am probably making more of this then i should and just hang it on the wall but i sure am baffled and want to learn a little on the way. sure appreciate everyones input. And please know i am being safe - i dont fire this near my face and actually have this mounted and pulling the trigger off to the side. anyway the 2 things i changed were the coal and full length resize backup off. hmmmmmmm.
Jim Watson
Member
It is still showing a stretch ring and might not last but another shot or two.
kaferhaus
Member
Back the sizing die out a full turn. Size a piece of brass and see if it chambers in the rifle. If it does, check to see if the neck has been sized enough to hold a bullet. If it has, reload that case, fire it and check it for the ring.... bet it's gone.
Typical excessive headspace problem.... find out how much minimal sizing you need to do for the brass to still chamber and your headspace issue with that brass is over.
Typical excessive headspace problem.... find out how much minimal sizing you need to do for the brass to still chamber and your headspace issue with that brass is over.
243winxb
Member
You need to be able to measure how much your backing off. A feeler gauge can be put between the shell holder and FL die when setting it up. If you dont have a feeler gauge, cut 5 shims made from a soda can. Each will be about .003" to .004" thick. Put a hole for the decapping pin in the middle. Size a case with about .015" between the shell holder & FL die. Then see if case will chamber before loading. The bolt should turn a little hard for a snug fit of the brass in the chamber.
243winxb,
I saw the case head separation pictures you posted under the title "Arisaka Model 38 6.5x50 - Bulge in cartridge" . I need some help if you don't mind, I am seeing that exact problem in my reloaded brass for my .303 British MK 1 NO 3. I reloaded some sellier and bellot once fired cases with a 174 grn fmjBT bullet and 38.5 grns of IMR 4064 powder and on the firing with the cases I saw the exact same thing you have in the pictures - some cases just have a crack around the back and others came right off. Do you know what is causing this? I posted under http://www.thehighroad.org/showthread.php?t=556060 this thread. Hope you can help.
I saw the case head separation pictures you posted under the title "Arisaka Model 38 6.5x50 - Bulge in cartridge" . I need some help if you don't mind, I am seeing that exact problem in my reloaded brass for my .303 British MK 1 NO 3. I reloaded some sellier and bellot once fired cases with a 174 grn fmjBT bullet and 38.5 grns of IMR 4064 powder and on the firing with the cases I saw the exact same thing you have in the pictures - some cases just have a crack around the back and others came right off. Do you know what is causing this? I posted under http://www.thehighroad.org/showthread.php?t=556060 this thread. Hope you can help.
Yes Mr. Watson you are right the right is still there and probably like you said get one more firing. I am going to try what kaferhaus recommended when i get home tonight and let all know. I sure have learned alot from everyones experience. Only got 2 more norma cartridges not fired left. Man that stuff is expensive from Midway. I would do the test now but the work thing is getting in the way. shesssh.
243winxb
Member
The brass is Stretching on firing.
Mookiie, Neck size your brass with a neck die. http://www.midwayusa.com/viewProduct/?productNumber=199697When the brass will no longer chamber you will have to use a full length sizing die. But control how much you push the shoulder back by placing a shim or feeler gauge between the shell holder & die when adjusting it. Start with a shim of .015", size your brass. Will it chamber with a little extra bolt pressure. If you can not close the bolt, try a smaller shim maybe like .012" or smaller till the bolt closes on the empty case. http://www.brownells.com/.aspx/lid=12897/GunTechdetail/Gauging_Success___Minimum_Headspace_and_Maximum_COL
Mookiie, Neck size your brass with a neck die. http://www.midwayusa.com/viewProduct/?productNumber=199697When the brass will no longer chamber you will have to use a full length sizing die. But control how much you push the shoulder back by placing a shim or feeler gauge between the shell holder & die when adjusting it. Start with a shim of .015", size your brass. Will it chamber with a little extra bolt pressure. If you can not close the bolt, try a smaller shim maybe like .012" or smaller till the bolt closes on the empty case. http://www.brownells.com/.aspx/lid=12897/GunTechdetail/Gauging_Success___Minimum_Headspace_and_Maximum_COL
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Ping, the measurement Jim Watson is referring to when measuring the effect the case has on head space is: Datum 3/8"/.375 to the head of the case 1.584. I went to the Big Town Gun Show two weeks ago and came home with 40lbs of datums, $20.00. It takes me less time to makeup a datum than it takes me to look one up. The .375 datum is the same datum used on the 30/06. 7.7 Japanese, 25/06 and 25+ other chambers, you don't have a .375 datum? Make one, drill a 'straight' hole in a metal block and...you are done, then there are improvements on that design but who would remember where they got the ideal, you do not have a drill, drill press and a means of drilling straight, go to a hardware store, a bolt supply store or somewhere they sell wire, Fastenall is a good place to start, and, Harbor freight, all sell plates with holes, some are plastic, others are metal, by what ever means once you have acquired the .375-3/8'th hole drop the case fired or unfired into the hole until it contacts the plate then measure the height of the protruding case above the plate, then write the measurement for for comparison after the case is fired, then measure the case again by placing it in the .375 hole and measure the height of the case above the DATUM, the difference should tell you the amount of stretch or effect the chamber had on the case when it was fired, same for sizing, before sizing drop the case through the hole and measure, THEN, size and measure again, the difference between the two measurements will indicate shoulder set back, and do not go for the "you need a neck sizer die" "You need a bushing die" first learn to get all the use you can out of the die you have, I prefer the versitle full length sizer die, it sizes, partial full body sizes, neck sizes with improvement in techniques and methods, I have all those other die, I refer to them as nice to have.
The diameter of the case can be measured, BUT, there seems to be some that believe I am trying to overload you, I have no clue as to their motive, I do not have five different ways to tell you if you are going to reload there are methods, techniques and knowledge you to need master, after a few years of correct practice I hope you do not take on the attitude your opinion is the only one that is important.
It was suggested you do a chamber cast,,,then in the same sentence it was suggested you check the cast of the chamber for head space, it can be done by a very few, one of the very few that can/has done that wouldn't.
F. Guffey
The diameter of the case can be measured, BUT, there seems to be some that believe I am trying to overload you, I have no clue as to their motive, I do not have five different ways to tell you if you are going to reload there are methods, techniques and knowledge you to need master, after a few years of correct practice I hope you do not take on the attitude your opinion is the only one that is important.
It was suggested you do a chamber cast,,,then in the same sentence it was suggested you check the cast of the chamber for head space, it can be done by a very few, one of the very few that can/has done that wouldn't.
F. Guffey
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mallc
Member
Flirtin with Disaster
You ought not shoot that gun until you have the chamber looked at. All the tinkering in world on the round won't fix a bad gun. A good bore scope can quickly answer your question. It's possible to cast the chamber but whatever is allowing the bulge may well lock the cast in the receiver and then you'll have a real mess!
You don't have to be in a hurry to solve this mystery...
Scott
You ought not shoot that gun until you have the chamber looked at. All the tinkering in world on the round won't fix a bad gun. A good bore scope can quickly answer your question. It's possible to cast the chamber but whatever is allowing the bulge may well lock the cast in the receiver and then you'll have a real mess!
You don't have to be in a hurry to solve this mystery...
Scott
Steve Marshall
Member
In your first set of pictures you can readily see that the brass expanded quite a bit ahead of the case. I would say that your chamber is grossly oversized there. That could be the way it was manufactured but not likely. More likely is Bubba polished the chamber.
NCsmitty
Member
I've been giving some thought to the "bulge" in the sequence of reloaded case.
Does it sound feasible that the bulge was formed in the sizing process when the case partially collapsed along the stretched fracture line and then fired?
I keep wondering how the strange ring in the cases had been formed, in the pictures that Ping had taken, if the chamber is smooth.
A thickness of case could push a ring out when fired.
There's no doubt in my mind that the rifle is at the least, experiencing headspace problems, and not being able to inspect the rifle, who knows what other issues it may have.
Has anyone else got an idea about the ring, as I had never seen anything quite like it.
NCsmitty
Does it sound feasible that the bulge was formed in the sizing process when the case partially collapsed along the stretched fracture line and then fired?
I keep wondering how the strange ring in the cases had been formed, in the pictures that Ping had taken, if the chamber is smooth.
A thickness of case could push a ring out when fired.
There's no doubt in my mind that the rifle is at the least, experiencing headspace problems, and not being able to inspect the rifle, who knows what other issues it may have.
Has anyone else got an idea about the ring, as I had never seen anything quite like it.
NCsmitty
rattletrap1970
Member
Again, I wonder if the rifle was re-chambered and not marked. After reading this thread I punched mine indicating that is it now 6.5x55 (not 6.5x50)
Well I fired one of my original 156 grain norma cartridges and as usual there is no problem. With this said does that not indicate that the gun is not potentially a problem. anyway - I reload it and did like kaferhaus said and run the die down to the plate and then i backed it off 1 1/2 turn. I went a little more..... It did resize the mouth enough and i could chamber in the rifle also. I then primed and all loaded. I fired it ejected the shell and all looked fine. So - what does this indicate. Did I replicate the original cartridge as it has no problems either. one person said use a bore scope. Not sure exactly what that is. Is it just putting a light down the barrel and viewing. Not sure. Not sure what casting a chamber is. Sorry to ask all these questions but I just dont know.
fguffey: you said alot there and i got to digest that. datum and all. I know to many questions but gosh i want to know.
fguffey: you said alot there and i got to digest that. datum and all. I know to many questions but gosh i want to know.
NCsmitty
Member
Essentially you are compensating for the stretched brass by backing off on the full length sizing die so the brass is the size of the chamber. This reduces the sizing and stretching and eventual case separation that you observed previously.
This is not to say that your rifle is good, as I personally think that the headspace is too long and out of spec, and that's why you had the problem.
You should be very cautious, as you are not experienced and could have a problem if you continue to shoot the rifle without someone knowledgeable inspecting it for you. No one here wants that to happen.
Be safe!
NCsmitty
rcmodel
Member in memoriam
Post #3:
Post #23:
I'm still waiting for the OP to do this on a new once fired case.
I guess you can lead them to water, but you can't make them drink!!!
rc
Post #23:
I'm still waiting for the OP to do this on a new once fired case.
I guess you can lead them to water, but you can't make them drink!!!
rc
used a paper clip and I cannot feel anything different. Ok, so i understand a little more about how basically it is filling the chamber when not fully sizing. Well I will just put the rifle aside as a collectable i guess. Just funny how new ammo just shoots fine and not problems with the brass. I guess when i resize partially it is putting it back closer to how the original brass came. Is that a fair assessment. I will not continue to bore everyone with this. I do appreciate everyones help.
NCsmitty
Member
I can see that you are getting the basics here. The first time that you shot factory ammo, the case expanded to fill the chamber. If you had measured the case length before firing with a vernier, and then measure it after firing, you would see the difference in length in tangible numbers.
Then when you initially sized the case for loading, you squeezed the case back down to a shorter size again, and after firing, a more visible line around the case appeared as the case was stretched again, and the brass got thinner at the stretch line.
Now fast forward to when you shot the factory ammo a day or two later, but then you raised the die so it didn't shorten the case when you loaded it. The case fit the chamber and the case stretching was nearly eliminated. The fired round that you reloaded came out looking fairly good, as you mentioned.
So you see, the rifle does have an issue, but you can work around it by fitting the brass to the chamber. You just have to be cautious in not loading the cases too many times, and create a dangerous situation. Now you know what to look for when firing that Arisaka.
I'd still feel better if you had someone knowledgeable check it over.
NCsmitty
Then when you initially sized the case for loading, you squeezed the case back down to a shorter size again, and after firing, a more visible line around the case appeared as the case was stretched again, and the brass got thinner at the stretch line.
Now fast forward to when you shot the factory ammo a day or two later, but then you raised the die so it didn't shorten the case when you loaded it. The case fit the chamber and the case stretching was nearly eliminated. The fired round that you reloaded came out looking fairly good, as you mentioned.
So you see, the rifle does have an issue, but you can work around it by fitting the brass to the chamber. You just have to be cautious in not loading the cases too many times, and create a dangerous situation. Now you know what to look for when firing that Arisaka.
I'd still feel better if you had someone knowledgeable check it over.
NCsmitty
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Carl N. Brown
Member
If the chamber is oversize, stretch should show up more measuring base to shoulder, rather than base to neck; in fact if the neck of the fired case looks shorter than the neck of an unfired case the chamber is really oversized. (think firing a .308 in a 30-06)
NCsmitty
Member
Your right, Carl N. Brown, but Ping is a newbie reloader and giving him a reference point on the shoulder for a measurement might be an exercise in futility to show him that the excess headspace is growing the case after firing. The easiest for him was the overall case length. I don't know that he has a vernier to use.
NCsmitty
Have y'all considered that the Norma brass head diameter is grossly undersize compared to the chamber? I say this from seeing the same lopsided "bulge" back in `88 when I fired my FIL's 6.5 Jap reloaded using (that same) new Norma brass. The case ahead of the web tries to expand to the chamber walls but can't take the solid head with it -- case separates around the circumference right there.
IIRC addressed the problem by sizing/forming/trimming .243 cases (Head diameter 0.471" and using them instead.
Others' experience?
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ncsmitty - thanks for good info. I did learn something from this so that is good. I wish i had someone I knew to take it too and just have them look it over but dont really know of anyone in the area. Like you said if i shoot once and reload and full length like you said i should safely get 2 shots. I dont shoot this hardly ever. Got plenty of other guns i dont have issues with. just a good learning experience. I think i will though measure a new round before firing and see what the difference is. gosh those things are expensive though. i see midway has just the brass might try that and see what i get. again thanks all for the info and hopefully someone else reading this thread can glean some good info.
Jimfern
Member
I have a Arisaka 38 Carbine that I've reloaded brand new Privi brass for once. I noticed the same problem with my brass. My old Hornady manual says the brass should measure .447" at that area. When I resize with my RCBS dies, I measure it at .445". Shot out of the carbine, the brass measures .454" so my brass is expanding roughly .01". I bought it at a gun shop in East Texas a few years ago and it had been sporterized, although it looks like they only worked on the stock.
Is that similar to what you are seeing?
I went and pulled my rifle and it doesn't look worn out or abused (other than the sporterizing). In fact, almost all of the bluing is on the barrel/receiver is still there, so I'm wondering if this is a design feature and may explain why there are two vent holes in the receiver. Just my two cents, but I think I'm going to get the head space checked on it before I shoot it again.
Is that similar to what you are seeing?
I went and pulled my rifle and it doesn't look worn out or abused (other than the sporterizing). In fact, almost all of the bluing is on the barrel/receiver is still there, so I'm wondering if this is a design feature and may explain why there are two vent holes in the receiver. Just my two cents, but I think I'm going to get the head space checked on it before I shoot it again.
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