Hi guys, picked up a really nice SVT 40 on the EE. Don't believe I've ever had a gun with an adjustable gas setting before, I thought I read somewhere that the numbers work well with certain types of bullet weights. Was there a post on that or am I imagining it, anyways, I don't plan on using corrosive, never have never will.
svt 40 gas setting and bullet weight
- Thread starter tdod101
- Start date
Hey there, try leaving it at the setting it is on and try it out with whatever ammo you have, then go up or down according to your preference.
They usually seem to be set at 1.3 which seems to work for most. I would make sure that the gas passage hole is clean.
I don't think there is a thread about settings for different bullet weights. Nice that you are highly valuing your SVT-40 by not using corrosive.
Corrosive is the only thing I shoot because of cost, but I also like cleaning guns, so it is a win-win for me.
gewehr76
CGN Ultra frequent flyer
SVT is ment to operate with m1908 spitzer type bullet. So millitary fmj feed much more reliably than non spitzer type ammo which may be SP, round nose or semijacketed that can get hung on feed ramp or chamber throat. They will fire all type of bullet as long as you set your gas setting to feed particular ammo brand or type reliably. Sights are ysually set for 147gr lps type ammo so look for 150gr or simillar type that has spitzer type of ogive.
Then again ,each rifle is different so trial and error with all available ammo brands will give you an idea which is good or bad for you. Cost will quickly show you which brand of ammo to feed your gun
Then again ,each rifle is different so trial and error with all available ammo brands will give you an idea which is good or bad for you. Cost will quickly show you which brand of ammo to feed your gun
It isn't so much about the bullet weight as it is about the powder charge.
Most of the commercial ammo in 54R that I've come across and fired have projectiles at the high end of bullet weight for 54R (185-205gr) with lead cores and soft points (basically, hunting ammo). But they're invariably loaded light on powder, with relatively low impact at 100 yards (by up to 12 inches compared to military surplus ball ammo). This in and of itself isn't an issue with the SVT, because the front post is adjustable for elevation.
But the lower powder charge does mean I have to open up the gas a bit for the rifle to cycle reliably. On my SVT, I can cycle pretty much all military surplus at gas setting 2, but need to move it up to 3 for it to cycle the commercial ammo.
There's a reason why the commercial ammo tends to be loaded a bit on the light side. 54R has been around for over 120 years, and there's a VAST range of firearms floating around, of varying ages, manufacturing quality, and level of maintenance, chambered for the round. Commercial ammo manufacturers have collectively moved to err on the side of caution when producing ammo - for safety reasons. They simply don't know how old or good of condition the firearm that's going to use the ammo is going to be in.
The rule of thumb is to set the gas as low as you can, while allowing the rifle to cycle properly. And this will take a bit of trial and error.
Get a gas adjustment tool and sight adjustment tool - you'll need both in the long run.
This is a pretty good set that also includes a cleaning jag that fits on the cleaning rod that will come with the rifle, a Mosin/SVT "multi-tool" that also works as a go/no-go headspace gauge, and an oiler bottle:
https://www.corwin-arms.com/product/svt-40-tool-set-0
You can saving a whopping $10 by just getting the sight tool and gas tool:
https://www.corwin-arms.com/product/svt-40-essential-tool-set-0
I would also consider getting a stainless steel gas cup and piston. Even with non-corrosive ammo, the cup and piston are the two parts most prone to rust and wear and tear. The stainless steel new manufacture cup and piston set also have a perfect spec seal, so in a lot of cases, that means you can dial down the gas setting a notch or two - the originals on the surplus guns are all within acceptable tolerances, but might have just a bit of leakage, which forces you to a higher gas setting to compensate.
https://www.corwin-arms.com/product/svt40-stainless-steel-gas-pistoncup-set
Cheers, and enjoy the new toy. And... Well... Make sure your hearing pro is in good working order. The SVT packs a heckuva blast for the shooter. It isn't just the actual sound level, but the rearward directed pressure wave from the muzzle brake that you have to contend with.
Most of the commercial ammo in 54R that I've come across and fired have projectiles at the high end of bullet weight for 54R (185-205gr) with lead cores and soft points (basically, hunting ammo). But they're invariably loaded light on powder, with relatively low impact at 100 yards (by up to 12 inches compared to military surplus ball ammo). This in and of itself isn't an issue with the SVT, because the front post is adjustable for elevation.
But the lower powder charge does mean I have to open up the gas a bit for the rifle to cycle reliably. On my SVT, I can cycle pretty much all military surplus at gas setting 2, but need to move it up to 3 for it to cycle the commercial ammo.
There's a reason why the commercial ammo tends to be loaded a bit on the light side. 54R has been around for over 120 years, and there's a VAST range of firearms floating around, of varying ages, manufacturing quality, and level of maintenance, chambered for the round. Commercial ammo manufacturers have collectively moved to err on the side of caution when producing ammo - for safety reasons. They simply don't know how old or good of condition the firearm that's going to use the ammo is going to be in.
The rule of thumb is to set the gas as low as you can, while allowing the rifle to cycle properly. And this will take a bit of trial and error.
Get a gas adjustment tool and sight adjustment tool - you'll need both in the long run.
This is a pretty good set that also includes a cleaning jag that fits on the cleaning rod that will come with the rifle, a Mosin/SVT "multi-tool" that also works as a go/no-go headspace gauge, and an oiler bottle:
https://www.corwin-arms.com/product/svt-40-tool-set-0
You can saving a whopping $10 by just getting the sight tool and gas tool:
https://www.corwin-arms.com/product/svt-40-essential-tool-set-0
I would also consider getting a stainless steel gas cup and piston. Even with non-corrosive ammo, the cup and piston are the two parts most prone to rust and wear and tear. The stainless steel new manufacture cup and piston set also have a perfect spec seal, so in a lot of cases, that means you can dial down the gas setting a notch or two - the originals on the surplus guns are all within acceptable tolerances, but might have just a bit of leakage, which forces you to a higher gas setting to compensate.
https://www.corwin-arms.com/product/svt40-stainless-steel-gas-pistoncup-set
Cheers, and enjoy the new toy. And... Well... Make sure your hearing pro is in good working order. The SVT packs a heckuva blast for the shooter. It isn't just the actual sound level, but the rearward directed pressure wave from the muzzle brake that you have to contend with.
tdod101: I've had very good results in my SVT's with Wolf 174grn FMJ but my best groups have been made with PRVI 182grn. With the latter I get 1.5-2.0 inch 5 shot groups with a "sniper" version. Some people suggest you shouldn't use heavy bullet ammo in SVT's but when I use it I'm shooting fairly small numbers of rounds for accuracy testing. For simply blazing away I've got plenty of corrosive light ball. Regarding gas settings, the gun wasn't intended to have one setting for all conditions. Users were supposed to change settings as required by temp, fouling, etc. Varying your greasing of key points on the bolt can also affect function. I use wheel bearing grease on mine but reduce the amount in colder weather. These are great rifles- my most reliable one now is my $200.00 Lever Arms gun.
