1720T thread!

[Larcat]

There's not nearly as much info on these lovely guns on the internet as I'd expect. Thought I'd get one going.

Post setups, picture, tips, tricks and questions!

Here's mine: Corcoran furniture, tuned by Mike at TKO who also provided my moderator and the carbine extension. I replaced the aluminum butt pad with an old model Wokbutt. I'm running an Immersive Optics 5x24 with a single 1.26" BKL doublestrap ring. The stock mounts didn't quite fit right -- they impinged the loading area of the breech.

This is the easiest to shoot gun I've ever owned. Point and shoot.

It shoots Polymags at just under 800 and is an absolute laser.

Question: Would love to hear anyone's experience regulating rhese guns, is it worth it? Etc.

 

[Franklink]

The 1720T is a really underrated gun!

@SAZ dropped a regulator in his and tuned pretty extensively. I'd always assumed that with such a small volume air tube to begin with, the benefits of installing a regulator would be eaten up by losing that air volume to the space the reg took up. But he was able to make some meaningful gains in consistency and shot count. Hopefully he'll come along and give some better details for you.

 

[Larcat]

The 1720T is a really underrated gun!

@SAZ dropped a regulator in his and tuned pretty extensively. I'd always assumed that with such a small volume air tube to begin with, the benefits of installing a regulator would be eaten up by losing that air volume to the space the reg took up. But he was able to make some meaningful gains in consistency and shot count. Hopefully he'll come along and give some better details for you.

I fill to 2750 and shoot down to about 1500 and dont have any real POI movement -- above or below that though is noticeable, so I'm pretty curious about the reg

 

[mackeral5]

Here is my version of a 1720T. Currently tuned for 3-4 mags at 12fpe. I milled the breech for use with Mrod style mags, using an end mill in my drill press. Huma regulated with the larger plenum, sub 10gram peek hammer, peek poppet with 2mm stem diameter. The Rapid 70 bullpup kit was not very easy to shoot in as delivered form. I converted the pistol grip to use an AK style grip nut for ease of attachment with an adapter for using AR grips on an AK... This resulted in greater distance between backstrap and trigger. This improved trigger ergonomics significantly. I added a shotgun butt pad that I had lying around. Now it shoulders nicely. Prior to these 2 mods I was unhappy with the Rapid 70 kit and on the verge of selling it....the In the pic it has a 12 shot mag for a Umarex Synergis.

It is UGLY, but carries/shoulders/shoots very well.

 

[SteveV]

I really like mine as it's very accurate. I wanted this gun to behave more like a 2000 psi fill gun, so I swapped the spring INSIDE the valve for one from a Benjamin Maximus.

Cut the tube to 10 inches and added a drop block and bottle, reg set at 1500 psi for just under 18 fpe with AA heavies at 885 fps.

EDIT: Used a 21" DISCOVERY barrel purchased from Alchemy Airwerks. It is well prepped with an actual target crown. I have two.

 

[AirNGasman]

All chronograph numbers in the attached file are in this sequence- Low Velocity, High Velocity, Extreme Spread, Standard Deviation, Average FPS/FP.

View attachment 1720T pdf.pdf

 

[jwhayward]

I have one that I shot aaft with extremely accurate no need for regulator

 

[SAZ]

Here's the current tune on my 1720T......
I fill to about 3000-3100 psi then shoot about 30 to 35 shots then refill, rinse & repeat
I opted to remove the gauge when I installed the Huma regulator so I can't tell you how many psi I shoot down to, but I can tell you that after the 45 shots the poi starts dropping like a rock.
It's getting kind of late here so I'll try to take a picture tomorrow and get it posted here.

 

[Larcat]

Here is my version of a 1720T. Currently tuned for 3-4 mags at 12fpe. I milled the breech for use with Mrod style mags, using an end mill in my drill press. Huma regulated with the larger plenum, sub 10gram peek hammer, peek poppet with 2mm stem diameter. The Rapid 70 bullpup kit was not very easy to shoot in as delivered form. I converted the pistol grip to use an AK style grip nut for ease of attachment with an adapter for using AR grips on an AK... This resulted in greater distance between backstrap and trigger. This improved trigger ergonomics significantly. I added a shotgun butt pad that I had lying around. Now it shoulders nicely. Prior to these 2 mods I was unhappy with the Rapid 70 kit and on the verge of selling it....the In the pic it has a 12 shot mag for a Umarex Synergis.

It is UGLY, but carries/shoulders/shoots very well.

Wow, impressed with the mag conversion. Was it dicey, or straight forward?

 

[Larcat]

I really like mine as it's very accurate. I wanted this gun to behave more like a 2000 psi fill gun, so I swapped the spring INSIDE the valve for one from a Benjamin Maximus.

Cut the tube to 10 inches and added a drop block and bottle, reg set at 1500 psi for just under 18 fpe with AA heavies at 885 fps.

View attachment 308336

What barrel did you swap in here?

 

[Larcat]

View attachment 308345

All chronograph numbers in the attached file are in this sequence- Low Velocity, High Velocity, Extreme Spread, Standard Deviation, Average FPS/FP.

View attachment 308344

Nice furniture --- Vernon Austin?

 

[Larcat]

Here's the current tune on my 1720T......
I fill to about 3000-3100 psi then shoot about 30 to 35 shots then refill, rinse & repeat
I opted to remove the gauge when I installed the Huma regulator so I can't tell you how many psi I shoot down to, but I can tell you that after the 45 shots the poi starts dropping like a rock.
It's getting kind of late here so I'll try to take a picture tomorrow and get it posted here.
View attachment 308367

Well, you've certainly got it shooting tight. Any foibles or wrinkles in installing the regulator?

 

[mackeral5]

Wow, impressed with the mag conversion. Was it dicey, or straight forward?

It is straight forward but not very refined. One has to be willing to risk ruining the breech and having to buy a replacement.... A simple slot cut in the breech then the bottom of Mrod mags needs to be clearanced a bit. due to the close barrel to tube distance there is not enough meat in the breech to machine deep enough for unmodified MRod mags.

I was concerned with loosing accuracy when going to a mag, thankfully there was no discernable difference.

It's not the prettiest, but it works very well.

 

[AirNGasman]

"Nice furniture --- Vernon Austin?"

His grips, refinished with the bullet-proof Fullerplast I used to finish custom longbows and recurves with; in order to get the soft lustre I prefer. The fore-end was inlet and rough shaped by a buddy, then I finished the shaping and Fullerplasted it (also).

 

[boscoebrea]

It is easily one of the best PCP's made ,and the best bargain in air gunning for pistol shooters,or maybe the Crosman 1701 is,
Green one.

 

[Larcat]

It is straight forward but not very refined. One has to be willing to risk ruining the breech and having to buy a replacement.... A simple slot cut in the breech then the bottom of Mrod mags needs to be clearanced a bit. due to the close barrel to tube distance there is not enough meat in the breech to machine deep enough for unmodified MRod mags.

I was concerned with loosing accuracy when going to a mag, thankfully there was no discernable difference.

It's not the prettiest, but it works very well.

Pretty enough! I certainly wouldn't want to attempt it personally without a milling machine though

 

[Larcat]

It is easily one of the best PCP's made ,and the best bargain in air gunning for pistol shooters,or maybe the Crosman 1701 is,
Green one.

View attachment 308513

Try it in carbine config sometime -- like I said, it's the easiest gun to shoot I've ever tried and I've hsd well sorted CZs, shot some high end rifles, etc. Thing is like a lazer pointer within 50.

 

[boscoebrea]

I like the Prod in the carbine; I like to shot a pistol with one hand and I do rest it.....Carbines,I love them waaaay better than bullpups.

 

[mackeral5]

I like the Prod in the carbine; I like to shot a pistol with one hand and I do rest it.....Carbines,I love them waaaay better than bullpups.

I've never been a very good pistol shooter. 2 handed on a rest and I am decent. My one handed pistol shooting is almost comical. But I do like short shoulder fired guns, including carbines. For my Prod/1720 based guns I have 2 identical powerplants/tubes/trigger systems the uppers can swap between. One is in the above pictured bullpup. The other uses a Gen 1 Mrod trigger and old QB78 stock.

1720T Carbine

Prod Carbine

 

[boscoebrea]

Nice!