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Spring Kits For A 27a1.


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#1 TN.Frank

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Posted 25 September 2004 - 08:18 PM

Does anyone make a kit with the recoil and hammer spring that would be lower power then the stock ones in my Auto Ord. 27a1? I really don't want to cut the springs if I can help it, I just think that a couple pound lighter would help the bolt blow back enough to re-cock the action. Right now the UMB 230gr. ball ammo that I'm using doesn't have enough power to kick the bolt back enough to re-cock the gun. What are the stock Lbs. weight of the springs and what lbs. should I use as a replacement? blink.gif
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#2 Norm

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Posted 25 September 2004 - 08:31 PM

Dave Janowski is working on a spring kit for the 27A1. From what I undertand the springs are much lighter tension. It uses a buffer with lighter springs.

I think he is still working with the leagal "mumbo-jumbo" that is required before selling it.

If your 27A1 has new springs in it, it could need a couple hundred rounds to soften them up. Mine did.

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#3 TN.Frank

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Posted 25 September 2004 - 08:40 PM

Funny you should mention Dave. I did a google search and came up with some older pages to this forum where he talked about them. I've got the gun hitting good with the M1 sight and I've got it set up the way that I like it but it just won't "blow back" enough to allow the action to re-cock. I could probably use hotter ammo, maybe something in the +P range but I really don't want to damage the frame by using hotter ammo. I've been kicking around the idea of selling this gun and building up an AR in 45acp but I really would like to make sure it works right first. I e-mailed Dave, I'll wait for his reply and see if he's got his springs on the market yet. Thanks, talk to ya' later. wink.gif
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#4 PK.

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Posted 27 September 2004 - 07:17 AM

I would be very surprised if your gun was actually short cycling Frank, what exactly happens? Do you end up with an unfired cartridge in the camber and the firing pin not cocked? Has the empty from the previous round ejected?

Try this; De-grease the top of your receiver with alcohol or acetone, etc. Remove the springs but put the guide plate back in, move the bolt with the actuator installed all the way back to the rear of the receiver. Mark the position of the back edge of the actuator with a sharpie marker, crayon (or something) on top of the receiver. Reassemble the gun with all parts and load & lock. Now stick a piece of masking tape on top of the receiver with the forward edge 1” forward of the mark you made. The tape should bridge the actuator slot. Shoot. If the bolt is going all the way back it will break the tape. Repeat this procedure until you get the malfunction again. If it malfunctions and the tape is broken, it’s not short cycling.

HTH

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#5 TN.Frank

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Posted 27 September 2004 - 10:20 AM

QUOTE (PK. @ Sep 27 2004, 07:17 AM)
I would be very surprised if your gun was actually short cycling Frank, what exactly happens? Do you end up with an unfired cartridge in the camber and the firing pin not cocked? Has the empty from the previous round ejected?

Try this; De-grease the top of your receiver with alcohol or acetone, etc. Remove the springs but put the guide plate back in, move the bolt with the actuator installed all the way back to the rear of the receiver. Mark the position of the back edge of the actuator with a sharpie marker, crayon (or something) on top of the receiver. Reassemble the gun with all parts and load & lock. Now stick a piece of masking tape on top of the receiver with the forward edge 1” forward of the mark you made. The tape should bridge the actuator slot. Shoot. If the bolt is going all the way back it will break the tape. Repeat this procedure until you get the malfunction again. If it malfunctions and the tape is broken, it’s not short cycling.

HTH

That tape idea is a good one, I'll have to try it. The reason that I think it's short cycling is because everything works except the firing pin doesn't get captured by the hammer to cock the gun.
Hears an idea, can I cock the gun and listen for where the firing pin and trigger engauge then mark that spot then use the tape at that spot. This will tell me if the bolt is traveling back far enough to allow the firing pin and trigger to engauge. If the tape is broken at the spot where they engauge but the firing pin wasn't captured by the trigger then it's something in the firing pin or trigger, if on the other hand, the tape isn't broken then the bolt isn't coming back enough to let the firing pin and trigger engauge.

Do you end up with an unfired cartridge in the camber and the firing pin not cocked?=Yes.
Has the empty from the previous round ejected?=Yes.

I'm going to give the tape a try to see how far back the bolt is actually moving. That's a very good idea.
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#6 deerslayer

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Posted 27 September 2004 - 11:47 AM

Is the primer dented? Sounds like you could have a gun that is just short of going full auto which would be bad news.
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#7 TN.Frank

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Posted 27 September 2004 - 03:22 PM

Well, I put tape on the reciever to check the bolt travel and it's coming back more then enough to re-cock the firing pin. But, for some reason it's not catching the re-cocking it. Why do you think the firing pin isn't catching the trigger and being held back to re-cock the action? What do you think I can do to fix it? Is there any other checks I need to do to check the action for proper function? At least we know that the bolt is traviling back far enough, it's just that the firing pin isn't being held back in the cocked position. This is a puzzelment for sure. Any more ideas PK. If anyone can help me fix this problem you can so let me know what ya' think.
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#8 PK.

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Posted 27 September 2004 - 05:15 PM

Check the sear spring and make sure the sear isn’t binding on anything (like the disconnector. Make sure the sear/ firing pin interface is OK.
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#9 TN.Frank

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Posted 27 September 2004 - 05:29 PM

QUOTE (PK. @ Sep 27 2004, 05:15 PM)
Check the sear spring and make sure the sear isn’t binding on anything (like the disconnector. Make sure the sear/ firing pin interface is OK.

You dang near read my mind. I pulled it apart and took a look at the lower and how the trigger, sear and all function. The sear on the trigger was real rough so I pulled it all apart and polished up the face of the trigger sear and the sear that engauges the firing pin. This helped out quite a bit, especially on the trigger pull BUT I found out what the REAL problem is. The bolt isn't coming all the way back into battery(and like a dummy I'm cutting off springs, LOL) all I did was push the bolt forward a tad and it'd fire then push it forward again and BANG , it'd fire again. I either need to find out where the bolt is binding and polish that so it won't bind OR put in stiffer recoil springs. I may be able to put some small washers at the base of the recoil springs to shim them up a bit, that will stiffen it up and make it run until I can get some rounds thru it and let the action polish it's self up a bit.
I'd still like to check out David's lighter springs and buffer kit so it'll cock easier but until then at least I know what's going on, not going into battery. I'll get it worked out. I wish I'd have went to gunsmithing school, I really think I've got a knack for working on guns. Oh well, live and learn, LOL Thanks for the help PK, talk to ya' in a bit. cool.gif
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#10 TN.Frank

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Posted 27 September 2004 - 07:16 PM

I cut a piece of 1/8" thinck leather to fit behind the recoil spring guide plate, that helped out some with the spring tention. The major source of friction is where the bottom of the bolt rubs on the top ctg. in the mag. When the action is un-cocked it's not that bad but when you cock the action the bolt will rub badly on the top ctg. in the mag.
How much of this area can be removed and still have the bolt be safe? I know that about the first 1/2" or so would have to stay intact to strip the ctg. from the mag. I think that two cuts, on an angle from the bottom would allow the bolt to slide over the ctgs. in the mag without touching them much. I'm going to get this gun working, with the M1 sight that I installed on it it's hitting POA and cutting some very tight groups, it's a excellent shooter, it just needs some fitting and it'll work ok, I'm sure of it.
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#11 LIONHART

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Posted 27 September 2004 - 07:26 PM

Could the Magazines be the cause of your problems?
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#12 TN.Frank

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Posted 27 September 2004 - 07:31 PM

QUOTE (LIONHART @ Sep 27 2004, 07:26 PM)
Could the Magazines be the cause of your problems?

I don't think so, they're new mags from Northridge, I paid $30 bucks each for them, they should work fine. As far as feeding and what knot they're great, it's just the way the bolt rubs on the ctgs. that's making a friction point. I think I can relieve cut the bolt where it rubs the ctgs. and take care of the problem but I'd like PK to chime in first to see if it's a safe thing to do. It seems like I've seen a mod like that done to a bolt before, can't remember where or for what gun though.
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#13 LIONHART

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Posted 27 September 2004 - 07:46 PM

Did you modify the Magazine Catch to accept Unmodified Mags, or does your '27A1 (Like the majority) use Modified Mags?
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#14 PK.

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Posted 27 September 2004 - 08:36 PM

Do not remove any metal form the bolt nose. Polish with fine emery (240 or finer) but do not cut metal away as you describe. Think of the millions of guns similar to yours that work just fine and have for 80 years, same magazines, same type of bolt nose, same cartridges.

Do not clip the recoil springs of semi auto guns- the bolt velocity is already to high- we have had this discussion ad-nausium. Buy some new springs ASAP.

The leather pad won’t hurt.

My $.02

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#15 TN.Frank

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Posted 27 September 2004 - 08:39 PM

QUOTE (LIONHART @ Sep 27 2004, 07:46 PM)
Did you modify the Magazine Catch to accept Unmodified Mags, or does your '27A1 (Like the majority) use Modified Mags?

I bought a modified mag catch so I can use unmodified FA mags. I removed my stock one and am going to keep it. All the parts that I've replaced I've put back to keep so I can restore the gun to it's original condition just incase it becomes a collectors item someday.
I did get to looking at it with the mag out. When the action was un-cocked all was fine but cocked and it would bind from friction. The colser I looked the more I saw that the firing pin was really rough. I pulled out the firing pin and beveled the edges and cleaned it up, took some burrs off of it, smoothed it some and put it back in. It's much smoother now, even with the mag in place. This is an earlier(1995) Auto Ord. gun, not a Khar Arms but it's still rough as a cob inside. I think I've got just about everything smoothed out. I'll put a few rounds thru it tomorrow ans see how it works, it should work fine now that all the burrs and rough edges are smoothed out. I'll keep ya' updated.
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#16 TN.Frank

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Posted 28 September 2004 - 10:21 PM

QUOTE (PK. @ Sep 27 2004, 08:36 PM)
Do not remove any metal form the bolt nose. Polish with fine emery (240 or finer) but do not cut metal away as you describe. Think of the millions of guns similar to yours that work just fine and have for 80 years, same magazines, same type of bolt nose, same cartridges.

Do not clip the recoil springs of semi auto guns- the bolt velocity is already to high- we have had this discussion ad-nausium. Buy some new springs ASAP.

The leather pad won’t hurt.

My $.02

Ok so I cliped the springs but the lether behind the spring guide should put the tention back that I took off by cliping a coil and a half off of it.

I did modify the bolt nose but didn't touch the first half inch of it where it strips the ctg. from the mag, just from there back. There is still alot of friction from the ctgs. in the mag and the bottom of the bolt nose, I polished it up with 400 grit so it's very smooth. The friction stops the bolt from closing that last mm or so, it's not much but it's enough to stop it from going into battery. I've not shot it since I've polished the bottom of the bolt nose so maybe it'll work ok now, I'll test that tomorrow.

I really would like to get it working, I don't have $120 bucks for a new bolt so I'll have to make what I have work.
I wish I had the money, I'd send this thing in to you PK and let you work your magic on it but I just can't afford it right now. I'd love to have the barrel cut back and have the comp moved back and pinned to have a 16 1/4" OAL barrel instead of the 18 1/2" OAL that's on it now.
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