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greywolf67nt
09-12-2014, 10:52 PM
I just decosmolined my new (?) SVT 40 took it to the range and got 3 shots out of it.
The first 2 didn't extract properly, had to cock it by hand, then the third just stuck in the chamber. I had to bring it home and tap it out using my cleaning rod.
I am using SCDS Ammo 148 grain steel cased copper washed. The last round, if you hold a straight edge up to it, is bulged.
Has anyone else experienced this or is it just the operator?

Strewth
09-13-2014, 12:10 AM
I am unfamiliar with that ammo. Having said that, what's your gas setting at? My shooter likes 1.3?


....just looking above, we don't have an SVT Sticky yet? Any volunteers? I know a little, not a lot.

Doug_M
09-13-2014, 06:02 AM
Check the chamber. There could be cosmoline, or worse, hardened cosmoline there. Not necessarily your issue, but it seems to be the number one reason for extraction issues.

Rory McCanuck
09-13-2014, 08:24 AM
Could you show us a pic of your bulged brass?
If it's a bit of a swelling above the case head, nothing to worry about.
If it looks like Kuato from Total Recall, you have a problem.

I like the idea of cleaning it again/more.
Cosmo is pretty tenacious, boiling water straight from the kettle works well.

greywolf67nt
09-13-2014, 09:57 AM
The bulge isn't big enough to show up in a pic. Just enough around the base to firmly stick it in place.
I will take my brass brush and solvent to the chamber tonight and see what happens.
Does anyone know what size wrench the gas adjustment takes? The salesman, at the large sports store in Edmonton, wasn't very knowledgeable. I don't think I got everything I should have, including the wrench and sight tool.

Rory McCanuck
09-13-2014, 06:48 PM
Seriously, boiling water.
Wear a glove to protect your hand.
Pour it into the chamber, and the heat will loosen the cosmo, and the water will flush it out.
Then a swab of solvent to convince yourself it's clean, then a light oiling.

I think some of the SVTs even had fluted chambers?
If it's just a little bulge at the web just above the head, don't worry.
Chambers vary quite a bit, I have a Rem 7600 that bulges brass something fierce.
Accurate though, and by gently sizing I've gotten 4 reloads out of the brass so far.

greywolf67nt
09-13-2014, 07:27 PM
How do you post a pic on here?

Rory McCanuck
09-13-2014, 07:35 PM
You need to upload them to an online host, like photobucket, tumblr, there's lots of them.
Then you link the pic and it shows up on the page.
Not as convenient as some sites, but it's what we've got ;)

kennymo
09-13-2014, 07:45 PM
The tools typically don't come with the SVT's. I don't think there are too many originals left, most of what you see are aftermarket reproductions. The gas adjustment is five sided, so a standard wrench won't fit. Although some claim success with a small socket. I pop the adjustment out with the gas system apart and reinsert it turned where I want it.

kennymo
09-13-2014, 07:46 PM
And yes, make sure that chamber is good and clean. Dried up Cosmo can be a PITA.

greywolf67nt
09-13-2014, 08:13 PM
http://i1378.photobucket.com/albums/ah105/randyrose1/Mobile%20Uploads/IMG_20140913_183339-1_zps511a4aee.jpg
This is some of the spent shells.
I did notice this brown cruddy ring in the chamber so my wife's pasta pot is on the stove full of water and the whole frigging thing is getting submerged.
I hope she doesn't come home soon.

greywolf67nt
09-14-2014, 01:12 PM
After doing some more research it seems I am not the only one with this problem.
I guess some of the non milsurp ammo is to heavy a load and the case is weaker so it just expands a little too much.

Strewth
09-14-2014, 01:22 PM
Interesting pics. The cruddy brown ring is at the end where the cases are still shiny?

I dunno if you want to submerge the parts on the stove, melting cosmo has a definite aroma...when's your wife home? Does she love her pasta pot?
I just boil water and pour it down the barrel into a scrap bucket through a funnel? Kettle was $5 at Value Village, and the funnel was $1 at the dollar store...you can also attach a piece of tubing to a funnel to prevent boiling water splashing on the wood and hazing it white under the laquer.

greywolf67nt
09-14-2014, 06:04 PM
Yes the cruddy ring is where the shiny bit is on the shell.http://i1378.photobucket.com/albums/ah105/randyrose1/IMG_20140914_160750_zpsb7n3sg2g.jpg
I did some more research last night and I believe some of the chambers are fluted. Judging from the marks on the neck of this shell I think I have one of those. Apparently they are really fussy with ammo.
I soaked it for 1/2 an hour last night( yes in her pasta pot fortunately she loves milsurp) then took my 20 bore brush to the chamber.
I took it to the range today it would almost cycle properly with the gas adjustment set to 1.7.
I hope these issues go away once my surplus ammo gets here or else I have a new piece of art.

greywolf67nt
09-14-2014, 07:35 PM
I tried some of the ammo in my Mosin and it works perfectly so it won't go to waste.

Strewth
09-14-2014, 09:40 PM
Yeah, my shooter leaves cool marks on the neck from the fluting:)
How do you mean almost properly on 1.7? Still FTE? Hold it by your side, and see if the bolt slams all the way back? It should fling them good on 1.7.
How's your gas piston and cup? No corrosion?
Any other problems? I've heard the mag can affect extraction, but that apparently comes hand in hand with random stovepipes and poor feeding.

greywolf67nt
09-15-2014, 07:43 AM
It was like it didn't slide back far enough to hit the ejector.
I will have to wait a couple weeks now until the barge gets here with more ammo to see what it is doing.

Strewth
09-15-2014, 08:55 AM
Hum. If you're at 1.7 and it's still not kicking all the way back it could be a glitch farther into the gas system. The cup that the piston returns into is notorious for not being properly cleaned; at refurb yours should have been inspected and maybe replaced, but? Have you completely disassembled the gas system to check the holes are unobstructed? The piston does need to be fairly smooth as well to create a seal...I'm sure we can keep you busy until the ammo barge arrives:).

If parts are necessary...I dunno if we have access to SVT parts in Canada? I had to get a cleaning rod through Numrich; lots of parts, reasonable prices, silly shipping costs:(.
Maybe someone else knows.

Doug_M
09-15-2014, 09:12 AM
Is the line on the gas regulator lined up with the line on the block (should be at the top)?

http://i.imgur.com/V4yAf.jpg

greywolf67nt
09-15-2014, 06:44 PM
I am going to have to see if some one else in town has some ammo and try watching the action as it fires.
I think it boils down to the rounds sticking cuz when they stick (most of the time) they are STUCK. Like disassemble the rifle and pound it out with a cleaning road stuck.
And yes the lines are lined up now. They were a hair off before but I made sure last night to be careful.
I'm just gonna turn it into a sculpture and go buy another one but not from the same place.

Strewth
09-15-2014, 07:14 PM
Yeah, they get stuck good:). New ammo sounds like a great idea.

greywolf67nt
10-05-2014, 10:59 AM
Just got my crates of surplus on barge.
This thing LOVES nasty old surplus.
If I am reading the can right it is from 1968 but runs through my rifle like water.
My gas setting is at the max but should I be able to turn it down after a break in period?

Strewth
10-05-2014, 11:05 AM
I fiddled with mine at the range during my first outing IIRC? These are already pretty broken in?

Glad to hear you've solved the problem with "new" ammo. Sure is a hoot to blast through 5 rounds of Russian 30-06 in such a soft shooting rifle:).

kennymo
10-05-2014, 11:10 AM
I fiddled with mine at the range during my first outing IIRC? These are already pretty broken in?

Glad to hear you've solved the problem with "new" ammo. Sure is a hoot to blast through 5 rounds of Russian 30-06 in such a soft shooting rifle:).

And the noise and shocked expressions of everyone else on the firing line.....that's pretty fun too. I've packed it up a couple times after a couple mags when it's crowded, just to not be 'that guy', lol.

Strewth
10-05-2014, 01:51 PM
And the noise and shocked expressions of everyone else on the firing line.....that's pretty fun too. I've packed it up a couple times after a couple mags when it's crowded, just to not be 'that guy', lol.

Oh definitely:). Especially at my range right now; we've apparently elected to mitigate sound by putting the benches in sea-cans, but we haven't insulated them yet. Even my braked AR is bad, never mind SVTs and M44s:).

Doug_M
10-05-2014, 03:34 PM
Just got my crates of surplus on barge.
This thing LOVES nasty old surplus.
If I am reading the can right it is from 1968 but runs through my rifle like water.
My gas setting is at the max but should I be able to turn it down after a break in period?
It should run on 1.3 with 1.5 being the max you need to go. If you still have to run it on 1.7 its not the ammo.

greywolf67nt
10-05-2014, 06:10 PM
I can't tell you the exact words of the other 2 guys at the range used but they were colourful.
I have a Mosin Nagant and was expecting roughly the same kick. What a surprise when it was really no worse than my SKS thanks to the muzzle brake.

jfred
10-30-2014, 11:32 PM
Boiling water treatment on your chamber. Ensure the entire action/chamber/barrel is free of cosmoline. If that doesn't work deal with your gas settings. Start at 1.1 and work up from there

mr_jonny
10-31-2014, 01:46 AM
Mine hated the copper coated ammo. I only run surplus through, not many problems. I believe my brother and i went through a crate one day, no hick ups. ( he is from the states) . Ebay is where I got the wrench for it. Love the rifle it is my favorite!
I clean the chamber from the rear of the rifle, gas setting is 1.5, after market mags had to be filed to work in it. Don't forget to clean out you gas piston!