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I have a type 38 and the primers are backing out of the brass. The ammunition is factory loads. I suspect the head spacing is an issue. I had information how to make a home made head space gauge but cannot find it. From what I remember is a spend brass shell, strip the bolt and insert a piece of aluminum foil or brass on the face of the bolt. What I need is the thickness of the foil or brass to measure a no go gauge.
One question. Is the bolt matching, either by assembly number, or last three of the serial number depending on vintage?
Japanese rifles, Type 38 and Type99, are known to have "generous" chambers.
I would think that if the head spacing is too much to allow the primer to move, then the entire cartridge would move and you would experience hot gasses blowing past the case.
You just made me think of this PS, the T-38 and T99 have gas vents on top of the receiver and the safety knob is cupped to catch gas coming past the bolt in the rear. So you might not get the same blowback as with another design.
The bolt is NOT matching to the receiver. I have not noticed any blow back. Fired about 6 rounds and all but 1 of the primers backed out.
I agree Dean, and I did take that into consideration... but wouldn't you still notice the gas escaping from the vent hole? Either way, primers backing out is never a good thing, especially if the ammo is factory. If the bolt is not matching, then it could explain excessive headspace.
Do this... Disassemble the bolt and install it with the firing pin removed. Then, chamber a new round. Is the bold handle excessively loose when closed (can you rattle it around)?
I'm still curious. Is the bolt matched by assembly number, instead of last three of the serial number? That could be, depending on vintage of your rifle, a kangi mark+three digits. It will be on the bottom of the receiver, bolt root, front band, and other places. (The assembly number is not the same as the serial number.)Quote:
Originally Posted by 1mark
What I have done is using a bolt for another type 38 and a spent round. I removed the primer and attached 2 pieces of .0015 shim stock to the back of the round. The suspect bolt will close on the round with no resistance. Now using the other bolt it will not close on the round. I than removed one piece of .0015 shim stock. The bolt almost closed. So the suspect bolt is not good.
Now I need a type 38 bolt BUT it needs to be modified (bent handle) for use with a scope on the rifle. Anyone have one?????
I'm almost afraid to ask, What scope? Is this an add-on or are we talking a legitimate Type 97 sniper rifle?
Email Don Schlickman and ask him about your needs. dfsjpn@aol.com
No it is not a type 97. It is a 38 that was sporterized nicely and a scope added.
Whew! I thought maybe you were teasing us. Anyway, Don Schlickman bends bolt handles and also make repro parts for Japanese rifles. So maybe he can help you.
Good luck!
My T-99 sporter has a bent handle... although my dad (who sporterized it) had the handle cut and welded with a down turn - for what it's worth.
1mark, there are at least 3 different ways to determine the length of the chamber from the shoulder to the bolt face, because you have a Type 38 6.5mm50 I would suggest you use fired cases, Problem: You fired cases in the chamber and the cases did not form to the chamber. Meaning: Pressure was too low, pressure inside the chase should have expanded the case to seal the chamber. You do not have enough pressure to seal the chamber.
When I test Type 38 rifles I cover the receiver with a white towel/rag, after firing I look to see if escaping gas stained the towel, the last rifle I tested left to black stains on the towel.
If I wanted to check the length of a type 38 chamber I would neck up a few 6.5mm50 cases first, after necking them up I would start sizing them by adjusting the die off the shell holder with a feeler gage. I would start with .015" gap to increase the length of the case from the shoulder to the head of the case. If the case does not chamber reduce the gap to .010" and try again.
F. Guffey
Keep in mind if you reload you can correct headspace problems by just neck sizing. This works just fine as long as you only use these rounds with this rifle and is perfectly safe.
"If you reload"? a reloader that know what they are doing would know the length of the chamber before they left for the range. Not sure about the neck sizing, I have neck sizing dies, I do not use them but JIC. I have threads on my dies and in my presses. Threads allow me to adjust the die to, or off and or below the shell holder to control the length of the case from the shoulder to the head of the case.Quote:
Originally Posted by randy langford
F. Guffey
If you don't reload, you could have the barrel set back and chamber cleaned up. This is not as easy as on a Mauser or modern Rem 700. Metric threads, coned breech and extractor cut are a few of the hurdles.
The other option is to re chamber it to 6.5x57 or 6.5 Roberts. Mine was done in 6.5 Roberts and shoots wonderfully. Other options are 6.5x55 or 260. More work, but another option is 6.5 Rem mag.
I got fed up with the woefully undersized Norma brass a long time ago. Other makes share some dimensions with it. I make brass for my 6.5 Jap rifles from 30-40 Krag or .303 British. .303 has been the go to lately, as it's easier to find. I turn down the rim to .480 and that leaves enough for the cartridge to headspace on the .060" thick semi-rim like it's supposed to. Since I'm making them from a larger case, I get to set the shoulder where I want it also. I form them before trimming the rim down, then modify a 41 magnum shellholder to take the case for subsequent reloadings. If I was going to rehamber one, 6.5x57 would seem to be way to go, Sellior and Bellot is making ammo. With some added force and a bit of sizing die wax on the shoulder, it'll form down to 6.5x257 in the rifle using the bolt with innards removed. Some 6.5x257 rifles will be harder than others in this regard.
Bolts are hard to find and ebay "asking" price is $100. There is no guarantee that a different bolt will headspace better (longer). You could spend $100 and have the same problem. I have a bare receiver that I would like to put together but I will not spent $100 on a bolt.
I'm not familiar with the 7.7 bolts, but can a Type 99 bolt be modified for use in a Type 38??
Not no, but HELL NO! The recoil lugs on the Type 38 are monsters compared to those on the Type 99. I can visibly distinguish between the two just by looking at the recoil lugs even if they aren't side by side. A 99 bolt will rattle around in a 38. You could probably cut down a 38 bolt and make it work in a 99. Granted, the lugs aren't double or triple the size, but from a machinist standpoint on a part measured in thousandths of an inch......it is a massive difference. It can be done theoretically, but it is not in any way practical.Quote:
Originally Posted by cowboybart
You can mix and match firing pins and safeties if you use both and usually a hammer and maybe a dremel. I just parted out a rifle that had a 99 bolt and firing pin with a 38 safety. I had to use 3 hands, a vice and a screwdriver to get everything to line up right to get it apart. They had ground the back of the firing pin to make it all work. I had no heartache parting out that Bubba'd POS.
Well, now I know why Type 38 bolts are so expensive. I have never shot or even handled a Type 99. If I see the one hole in the front ring of the receiver, I pass it by.
The thickness of the semi rim on most factory ammo is a bit on the thin side in my opinion. I make my own brass from .303 or 30-40 with a .060 semi-rim. If the case of factory ammo goes all the way forward when hit by the firing pin, there's .010" headspace. There's a couple ways to keep the round from going all the way forward when struck. Maybe you can find a proper spacer with monofilament line, like they do rimmed .303. Or you could pull the bullets and seat them out into the rifling to hold the case to the rear. I have in the past greased the woefully small Norma cases so they wont grasp the chamber and will fireform back to the bolt face. Gotta remember not to set the shoulder back on those cases. I don't make a lot of 6.5x50, only one of my 38s still has it's original chamber, the others are 6.5x257.
I see I commented on this before, skipped that page earlier!
Head space: I am so lucky, my cases do not have head space. I use the length of the case from the datum/shoulder to the case head to off set the length of the chamber from the shoulder of the chamber to the bolt face. I do not expect anyone to understand any of that because it gets more complicated.
You have a protruding primer? What does that mean? It means you have clearance. The case is shorter from the shoulder of the case to the case head than the length of the chamber from the shoulder of the chamber to the to the bolt face.
Again, What does that mean? No one knows but the Shadow, he do. So someone should ask; "why is the primer protruding? Reason: The case head did not make it back to the bolt face when fired. WHY?
When fired the case locked to the chamber, with more pressure when fired the case would have stretched between the case head and case body. And that would have seated the primer.
I do not have any of these problems because I form my cases to fit the chamber.
And then it gets very complicated. (Back to clearance) I have fired rounds in my 8/06 chambers with .127" clearance; no protruding primers and no stretched cases between the case head and case body.
There are 'things I know' that a reloaders could do to understand what is going on when they pull the trigger; could do and 'do, most had rather talk tacky.
F. Guffey
OP is 6 years old.
"...home made head space gauge..." There's no such thing. A headspace gauge is a precision made instrument that does not measure anything. It's simply a Go/No-Go gauge that tells you if a rifle is within spec.
Quote:
Head space: I am so lucky, my cases do not have head space. I use the length of the case from the datum/shoulder to the case head to off set the length of the chamber from the shoulder of the chamber to the bolt face. I do not expect anyone to understand any of that because it gets more complicated.
"It's simply a Go/No-Go gauge that tells you if a rifle is within spec.."Quote:
OP is 6 years old.
"...home made head space gauge..." There's no such thing. A headspace gauge is a precision made instrument that does not measure anything. It's simply a Go/No-Go gauge that tells you if a rifle is within spec.
A go/no go gage makes two measurements, one will go and the other will not go. And then there is the go-gage that is used to measure the chamber from the shoulder to the bolt face. It is not job to convince anyone that chamber go/gages have been made to measure the length of a chamber from go/gage length to go/gage length plus .250".
I was asked to make a set of go-gages that were go-gage length +.023". I suggested the collector/reloader allow me to show him how to measure the length of the chamber in thousandths from the shoulder of the chamber to the bolt face at no cost. He had 18 8MM57 Mausers with no way to measure each one.
F. Guffey
Since you are a young reloader, you may not have all the tools a ailable to you that the test of us do, hopefully a parent can help or has at least a caliper.
The length of the backed out primer is the amount of headspace. For safety, it should not be over .010, preferably
005.
Use your caliper to measure a just fired, new case, if it is less than .005-008 you can fire form new brass to your chamber by reloading with 60-75% of max load to make the brass "fit" your chamber. You can measure headspace with the primer set back (ok) or by putting masking tape (better) on a new unfired cartridge head, remove firing mechanism, place the cart in the mag and let the bolt strip it into the chamber. Add tape until you feel resistance or you can't close the bolt all the way.
Last good bolt closure is your working headspace.
Edit: Iforhot to say measure thethickness of the layers of tape, that is the headspace.
The protruding primer indicates head space? The protruding primer indicates clearance. Someone was complaining about this thread being 6 years old; after all these years and still reloaders do not know how to identify head space.Quote:
The length of the backed out primer is the amount of headspace. For safety, it should not be over .010, preferably
005.
This is as slow as I can type; the protruding primer does not indicate clearance, the protruding primer indicates there is clearance.
F. Guffey
- - - Updated - - -
Head space is the distance from the datum to the bolt face.Quote:
Last good bolt closure is your working headspace.
F. Guffey
fguffy, have you published a book on headspace? If so how do I get a copy. I purchased a book titled “UNDERSTANDING HEADSPACE for FIREARMS. written by FRED ZEGLIN. It’s 52 pages of the best information I have read or had someone explain to me on headspace. By the way he doesn’t mention feeler gauges and all the extra comments you offer. Your comments are all bragging on how much you know and how stupid all other reloaders are and how superior your equipment is compared to other reloaders.
John in SC
Fguffey- Phil Sharp identified headspace as the distance between the cartridge head and the face of the bolt. He also said it could be called clearance meaning between the cartridge and bolt. He predated SSAMI I believe, and all the people I knew growing up, and still those I know now, understand for the reloader, headspace is the measurement of the distance between the bolt face and the cartridge head, most usually discussed for our reloaded rounds.
The measurement of the distance the primer protrudes from the head is a close approximation of what Phil Sharpe identified as "headspace". Using masking tape has/is an accepted alternate to find the distance between the bolt and cartridge, which most people understand to be headspace, but you prefer "clearance".
[Head space is the distance from the datum to the bolt face. [/QUOTE]
I agree with you on this statement.
John in SC
I can understand Phil Sharp writing a book about something he never saw before. Before SAMMI there were head space gages, they were the same as SAAMI gages with one exception. In the beginning they did not use 'the datum' they used the case body/shoulder juncture to the bolt face. It should not have been confusing because the old gages were stamped with the length of the chamber from the case body/shoulder juncture to the head of the gage. It should not have been confusing for a few because the shoulder, shoulder/neck juncture and mouth of the case were located in the correct place.Quote:
Fguffey- Phil Sharp identified headspace as the distance between the cartridge head and the face of the bolt. He also said it could be called clearance meaning between the cartridge and bolt. He predated SSAMI I believe, and all the people I knew growing up, and still those I know now, understand for the reloader, headspace is the measurement of the distance between the bolt face and the cartridge head, most usually discussed for our reloaded rounds.
I understand reloader believe I am calling them stupid; you understand it is impossible to fix stupid. Phil Sharp would have been doing reloaders a favor if he had said "I do not know". Reloaders have been trying to reinvent reloading by throwing 'head space' into ever conversation. Not me, there is something else besides 'head space' for example by design the length of the chamber is go-gage length, the case is said to be minimum length. If you are a fan of Phil Sharp the length of the case from the datum to the case head is not .005" shorter than a go-gage. And then we advance to go-gage length, after go gage length there is no such thing as field reject length.
And then there is my M1917 with a chamber that is .002" longer than a field reject length chamber, I understand there is no interest but a minimum length case has when fired in my M1917 has .011" clearance. And then I have to start over because of fans of Phil Sharp because he has convinced you and all the rest of his fans the clearance is between the bolt face and case head. The clearance on all of my M1917s is between the shoulder of the case and shoulder of the chamber.
Head space and case head separation: When I fire 30/06 ammo in one of my M1917 there is no stretch between the case head and case body. I know, it should not be necessary to explain that but no one understands the shoulder does not move and if Phil Sharp understood that we would not have so many confused reloaders.
F. Guffey
FRED ZEGLIN: If he did not mention the feeler gage he had limited shop skills. If the shell holder does not make it up to the bottom of the die the case did not get sized. If the reloader wants to know if the case had more resistance to sizing than the press/lube could overcome the reloader can measure the gap between the top of the shell holder and bottom of the die to determine the amount of the case that did not get sized.Quote:
By the way he doesn’t mention feeler gauges and all the extra comments you offer. Your comments are all bragging on how much you know and how stupid all other reloaders are and how superior your equipment is compared to other reloaders.
And then if the shell holder does not make it to the bottom of the die an advanced reloader can remove the die with the protruding case to measure the case head protrusion. If the case is returned to minimum length the case had will be protruding .125" because the deck height of the shell holder is .125". I doubt Old Fred would have been one of my fans.
F. Guffey
Fguffey- Yes, the gauges did exist before SSAMI began to define terms. They are used to make the rifle chamber. To the average reloader, and that does not mean stupid, they can not do anything about that. They are interested in making safe ammo with brass that will last as long as possible. That means making cartridges that fit that chamber as closely as possible, and that means removing, as much as possible, any gap (their rifle's headspace; your clearance), between the bolt and cartridge base either by intentional or unintenional fire forming thru repeated reloading.
We all know your "expertise" in reloading, and how you reload for your vaunted1917 with no cartridge headspace/clearance. We, also know your "expertise" in not being able to shoulder bump, however thousands of reloaders do so for their rifles.
This will probably result on your restating your previously published compendium on why everyone but you are wrong about reloading. I think I'll go to the range and join a few strangers that couldn't possibly have reloaded the rounds they are shooting safely and accurately.
I said it was impossible to move the shoulder back with a die that has full case body support, I did not say it sounded cool when a reloader claims he bumps the shoulder back. The same reloader claims his Rock Chucker cams over. I have three Rock Chuckers, not one of the three will cam over. Other reloaders, not one of them know/understands what it means for a press to cam over. Back to the part where it is cute to bump the shoulder. Bump is a function of a cam over press. If the press does not cam over it does not bump. BUT! if it did it would bump twice; once on the way up and again on the return trip.Quote:
We all know your "expertise" in reloading, and how you reload for your vaunted1917 with no cartridge headspace/clearance. We, also know your "expertise" in not being able to shoulder bump, however thousands of reloaders do so for their rifles.
The biggest bump press I have used was the A2 RCBS press. The cam over on that press was .037", I accused the owner of modifying the press. I had to show him how to adjust the cam over press when sizing cases. this was before the Internet.
F. Guffey
Phil Sharp is your hero, that is OK but a good case could be made to prove he did not know the difference between clearance and head space. Vaunted 1917? Not my 1917, back in the old days there were some very famous gunsmiths that got into a name calling hissy about my Vaunted 1917, I was 6 tears old. I got older and could not find out why they were so rude to each other. Anyhow I was able to put enough of the story to determine what happened. Nothing has changed, they could not figure out what and how he was doing 'what he was doing' and because they were so tacky he never did tell them what he was doing and how he was doing it.Quote:
We all know your "expertise" in reloading, and how you reload for your vaunted1917 with no cartridge headspace/clearance. We, also know your "expertise" in not being able to shoulder bump, however thousands of reloaders do so for their rifles.
F. Guffey
Fguffey- No, Sharpe is not my hero, my father has that distinction. Sharpe,s was the first reloading book I read, and while much of it has been overtaken by technology, the basic tennents temain the same. In fact, I've read either here or on another gun site, that Sharpe's character was much like what you demonstrate here.
Think I'll go do something more productive, like paint the patio.you can have the last word like you always try to do.
If you want to be productive try to move the shoulder back on a case when using a full length support sizing die. Start by scribing the case body/shoulder juncture.Quote:
Think I'll go do something more productive
Clearance and head space: I believe it would help if you would start with SAAMI.
As you know we had a member claim the case had head space, not my fault but he had a lot of time and gigs of space invested in his belief; problem, he never read SAAMI and he did not understand mechanical drawings. SAAMI does not mention case head space on their case drawings and they have no foot note that identifies head space for the case.
But he still insisted to the point it was embarrassing, after that he claimed he called SAAMI seeking relief. I guess they were impressed when he gave them his pedigree.
Last word? I believe we 'all' would be better off without that kind of comment.
F. Guffey
Mechanical drawings: Many years ago I upset the head space experts. They insisted head space was identified and located with a line, they even had an arrow pointing at the line identifying the line as head space.
I insisted the datum was a round hole and on a drawing it was a circle I even wasted my time telling them about the story of the Duke that gave away some of his Dukedom for anyone that could solve his riddle. I recreated the riddle and introduced it to one of the biggest high schools in Texas. They all failed.
F. Guffey