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Airforce What can I expect from a .257 LSS power kit upgrade?

What improvements exactly would I achieve with the .257 power kit. I operate a stock .257 LSS and tethered.
I shoot at 3000 psi at aprox 1000 fps with 72 grain slugs. I only shoot targets 200 + yards.

I want to upgrade my .257 LSS and wonder if the power kit will be helpful.

Has any Texan shooter installed this power kit and what were your results?

If you can keep your comments and suggestions "on topic" it would be appreciated.

Thank you in advance
Rodney Java
San Francisco
 
Reedmosser,
Great intel. Thank you. I reached out to 357cal for his insight on the upgrade kit.
Having the upgraded 4500 psi capacity is not issue with me since I shoot tethered.

I already know that a AVS 87 grain slug can reach out to 500 yards with my .257, so heavier slug is not needed for my range shooting.
 
That valve is only 250bar (3625 psi)
If you really want to flex there is the 300 bar (4500psi) valve from african air ordinance for the low low price of just $550.
4500 psi valve
1617295726147.jpg
 
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That valve is only 250bar (3625 psi)
If you really want to flex there is the 300 bar (4500psi) valve from african air ordinance for the low low price of just $550.
4500 psi valve
View attachment 371635
Thank you for chiming in. I decided to only upgrade the hammer and sprung since I shoot tethered.

Now, I'm looking for detailed instruction on how to replace these parts for the .257 LSS specifically.
 
Only 2 months ago, I splitting playing cards at 200 yards with my .257 LSS. I've done it several times with less than 10 shots. and with the RSO's and fellow airgunners verifying my claims.

Then suddenly all my groups started opening up. Nothing changed with my tune, slugs or tethered gear. I cleaned and polished the barrel and the groups got a little smaller, but not even close to splitting another card at 200 yards.

I thought about upgrading to a power kit as it might include new o-rings and such.
I figured out that since I shoot tethered, I don't need a larger tank or need to increase velocity as I would still be shooting the same slugs and setup

Now my thoughts are to only replace the spring and hammer., Then I decided to only change to a upgraded spring, which I now have on order. I don't think changing the hammer will make a difference.

Any thoughts about my plan to only swap springs? Is this enough to get be back to splitting cards at 200 yards?

Rod in San Francisco
 
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I don't think your accuracy will change or get better from the heavier spring. It may bring more problems . My big 50 is constantly inconsistent.. Know it does group consistently around 2-3 moa at 125 yards. But trying to consistently hit say a golf ball at 125 yards... Forget it. Texans have lots of vibrations.. I can only use Airforce BKL adapter on my rail. All others move with recoil. I'd check all your components to mount optics on rail. Also the thin barrel is in tension on the LSS make sure everything is tight. My Texan has was more recoil but I have learned a thing or 2 about weak points. Everything has to be tight on mine. Including Donny FL if it loosens any accuracy suffers. I use a oil filter wrench to tighten to same cam mark each time. Here to help
 
Reedmosser,
Thanks for chiming in. I have noticed more recoil to a point that I can't see the target POI through the scope after the shot. Seems like a heavy jerk type of recoil. Before, I can shoot and still see the POI. I got everything tight including my Cold Shot, moderator and scope. I use a Remple Fclass bipod which rest on a carpet pad. Finally I have a Mad Dog stock to stiffen it all up.

I have a few springs on order to try out. And will replace any o-rings if any, when I take apart the assembly to replace the springs. I doubt it's the barrel since I cleaned and polished it.


Thanks again for your help

Rod in San Francisco
 
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Reedmosser,
Thanks again for chiming in. Great intel.
I did order some 70 A durameter orings for my tophat. I don't have the TX2 valve on my .257 LSS. But no harm in replacing the orings.

I've been shooting with my Cold Shot for about 2 years without an adapter. As I thought the Texan had a picatinny scope rail. In any case, its torqued down just right and does not move or cause vibration. Like I mentioned, I can split playing cards at 200 yards. I do have a 12x60x60 scope. What scope are you using with your Cold Shot?View attachment 20230716_083407.jpgView attachment 20230716_083428.jpgView attachment top hat (1).jpg
 
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I have the same cheap adapter s from Amazon...I have a regular Sightmark Wraith HD 4-32 digital scope.. Its been ultra reliable for 3 years. Useless under 50 yards. At 125 yards I can see my .510holes. Not too bad for digital. You have accomplished much better accuracy than me. Keep after it.. Airgun s having a mood and temperate or there own.. Those adapters from Amazon won't take the recoil on my rig and did.move no matter how tight they are. Try the Airforce BKL adapter. Maybe its that adapter???? That adapter from Amazon with coldshot base setup I tried on my .510.....It failed... It would slowly slide forward shot after shot..
 
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