My AirMax PP700 Field Target Pistol Development, to Date...
Select Gate
READ GTA FORUM RULES BEFORE POSTING
GTA Forum Help Desk
GTA Announcement Gate
Dealer Area
GRIP
AirgunWeb Airgun Videos
Airgun Repository of Knowledge
Vendors and Vendor Videos
AirGun Expo 2021
Airgun Expo 2022
Contests and Giveaways!!!
Welcome New Members
In Memoriam
GTA Contributing Members
Shot Show Videos
Hajimoto Productions
Airgun Detectives
Air Gun Gate
BB Guns and Such
"Bob and Lloyds Workshop"
American/U.S. Air Gun Gates
European/Asian Air Gun Gates
PCP/CO2/HPA Air Gun Gates "The Darkside"
Air Archery
Vintage Air Gun Gate
Air Guns And Related Accessories Review Gates
Hunting Gate
Machine Shop Talk & AG Parts Machining
3D printing and files
Buyer's, Seller's & Trader's Comments
Bargain Gate
Back Room
Target Shooting Discussion Gate
Target Match Rules
Shooting Match Gates
Field Target Gates
The Long Range Club
100 Yard Match
Discussions By States
Welcome,
Guest
. Please
login
or
register
.
Did you miss your
activation email
?
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
Home
About
Help
Old GTA
Gallery
Search
Stats
Login
Register
Advertise Here
GTA
»
Target Shooting Matches, Discussion & Events
»
Field Target Gates
(Moderator:
Tpatner412
) »
My AirMax PP700 Field Target Pistol Development, to Date...
« previous
next »
Print
Pages: [
1
]
Go Down
Share This!
Author
Topic: My AirMax PP700 Field Target Pistol Development, to Date... (Read 5450 times))
DFWdude
Marksman
Posts: 308
Real Name: Bob
My AirMax PP700 Field Target Pistol Development, to Date...
«
on:
March 17, 2016, 09:29:59 PM »
My SPA PP700 has been set up for AAFTA Field Target Pistol. As such, the stock 9-1/2” barrel and shroud has been replaced entirely with a set of Crosman parts... A 12" LW barrel cut to 11-1/2”, fitted within a standard length Crosman shroud assembly, as found in a Crosman 1720T. Total barrel length (muzzle to breech face) is 14.1.”
The barrel is rigidly mounted to the frame via three 10-32 set screws. The rear-most of these uses an offset seat, as found in the Steyr LP10 match pistol. Introducing a conical set screw (shown atop the frame) permits fore-aft adjustment of the seal with the breech block, prior to locking the barrel in place with the two remaining screws.
New barrel, as installed (without shroud)…
I’ve used a variation on Scott’s springer breech seal. Instead, I used two, stacked BUNA o-rings, 2.4mm x 6.6mm (ID), mounted in place on a .312” stub on the barrel. These are then joined with a VERY light application of Super glue in the groove around the circumference between the two rings. This yields the secure (yet removable) placement on the barrel and fits perfectly within the space formerly occupied by the floating barrel bushing.
The Regulator pressure has been increased very slightly (I have no way to measure how much), and the hammer pressure reduced from stock, approximately one turn. The Poppet return spring in the valve was loosened .025” to allow a longer valve duration. The Transfer Port is fully open, flush with the top of the rotating breech.
So far, it shoots a flat string averaging 691fps, using JSB Exact Heavy (10.34gr) pellets, producing 11.0 fpe. Std Dev. Is 7fps, with an overall spread of 12 fps. I would say 30 usable shots per fill.
The pistol sports a UTG 3-12x 42mm short scope with etched-glass, mildot reticle. It is mounted in a set of self-centering, BKL 354MB offset rings (30mm). To achieve a proper fit, the dovetail rail on the pistol was shimmed with .030” brass angle stock on each side.
I've decided to have some fun, and Embrace the Green…
The forearm is of my design, 3D printed to nestle in a Bogpod Bipod. The entire pistol, as seen here weighs exactly 4 pounds, 0 ounces.
With its new barrel, it now shoots hole within hole at my desired first zero (17yds), astonishingly better than the stock barrel. It has to go some to displace my regular PFT pistol, a CZ200s/Pardini rifle hybrid. But I will give it a fair chance in the next few weeks to see how reliable it is with its iffy o-rings.
«
Last Edit: April 25, 2016, 08:21:35 PM by DFWdude
»
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
Motorhead
Field Target Shooter .... Stand em up Shoot em down
GTA Senior Contributor
Posts: 17753
2019 GTA Hall Of Fame Recipient
Real Name: Scott
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #1 on:
March 17, 2016, 09:42:12 PM »
Bob ...
There ya go, lots of ways to get to the same destination
Yea a GREAT barrel really makes these little pistols step up there game !!
Fore end ... we need to talk, am liking that a LOT
Good luck in the PHFT wars, am months away from any PHFT action out west & like you my Pistol used these past couple years is a tough one to derail. This PP700 has a pretty good climb to get into a replacement status.
We'll see
Logged
Northern California ... Old Hangtown
**
Home of MOTORHEADS AG Tuning Services
**
* PM me for further contact & tuning info.
Sacramento Valley Field Target Club
#
https://sites.google.com/site/sacvalleyairgunclub/
DFWdude
Marksman
Posts: 308
Real Name: Bob
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #2 on:
March 18, 2016, 04:34:51 PM »
Here's a golf tip.... Errrr, a shooting tip.... Whatever...
If you are a golfer, you have a simple tool in your bag that will serve to remove the valve from the frame. Any old Divot/Spike Repair Tool, with some judicious filing on the outer edges of the spike repair tongs, will fit the spanner holes in the valve outer face.
Just call this find an early Easter Egg...
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
DFWdude
Marksman
Posts: 308
Real Name: Bob
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #3 on:
March 19, 2016, 04:52:30 PM »
I think I will keep this Crosman Barrel...
10 shots at 20 yds,
AA 10.34s, in a 10mph lateral wind. One flier to the right.
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
Motorhead
Field Target Shooter .... Stand em up Shoot em down
GTA Senior Contributor
Posts: 17753
2019 GTA Hall Of Fame Recipient
Real Name: Scott
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #4 on:
March 19, 2016, 04:56:43 PM »
Indeed the 1701 10" and 1720's 12" LW barrels shoot well !!
Logged
Northern California ... Old Hangtown
**
Home of MOTORHEADS AG Tuning Services
**
* PM me for further contact & tuning info.
Sacramento Valley Field Target Club
#
https://sites.google.com/site/sacvalleyairgunclub/
DFWdude
Marksman
Posts: 308
Real Name: Bob
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #5 on:
March 21, 2016, 12:14:45 PM »
I'm been asked elsewhere for more information on the set of Crosman parts needed for this pistol, so here goes...
Crosman 1720T Parts list:
1720-T LW barrel = $70.90
Black Anodized Shroud = $17.40
Rear Barrel Mount = $8.00
Anodized Muzzle Cap = $4.93
Internal Barrel Stripper = $6.25
Baffle = $5.04 (ea)
Shipping = $4.00
Sales Tax = $7.28
Total = $123.80
Add a few miscellaneous O-Rings and 10-32 set screws, bluing to refinish Crosman's parts bin rust (huh?), etc., and you've spent around $130 in parts. Scope and mounts, 3-D printed foreend extra.
I shortened the barrel from the breech end in my lathe to remove the vertical transfer port, not used in the PP700. I had to do this twice, to correct an silly error on my part. Done correctly only 1/4" needs to be milled away, leaving 11-3/4"
Everything fits together in typical Crosman fashion. EXCEPT... Considering that 1) the standard Crosman barrel is machined, making it shorter, and 2) the through hole in the PP700 breech block is not the same length as in the 1720T... The finished barrel when mounted is a different length than OEM Crosman. So, this requires different number/length of baffles to fill the space in the standard length, Crosman shroud between the stripper and the shroud cap.
You can leave out all the baffles and have just one space between the stripper and the end cap. This cuts the "bark" fine as is. But if you want to soften the report more, you will have to fiddle with the number of baffles and their length, as each will be different. (I manufactured my own baffles on the lathe, so don't know how many factory baffles should be used.) HTH.
«
Last Edit: March 21, 2016, 12:23:22 PM by DFWdude
»
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
DFWdude
Marksman
Posts: 308
Real Name: Bob
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #6 on:
March 28, 2016, 09:52:27 PM »
After replacing all the cheap, Chinese o-rings with real (reliable) ones, I had good weather to do some additional tweaking today.
Previously, I was getting slowly ascending shot string velocities with the primitive regulator in this pistol. Today, I increased the reg pressure about 1/16th turn, and decreased the hammer spring pressure -1/4 turn. Don't ask how I arrived at these values, as I have no idea.
Finally, I am seeing a relatively flat string for 32 usable shots at 11.3fpe (JSB 10.34gr pellets).
I don't think this small reservoir will ever see more than 45 shots on a fill... I'm guessing the volume is 60ccs or less. So, I will resign myself to filling once a match (The Crosman 1720T shooters refill once, sometimes twice a match at the same power levels).
«
Last Edit: March 28, 2016, 10:04:41 PM by DFWdude
»
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
DFWdude
Marksman
Posts: 308
Real Name: Bob
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #7 on:
April 14, 2016, 01:20:19 PM »
I finally got around to tuning the trigger. Before this, I removed almost all the sear engagement and 1st stage travel, leaving a crisp, but very hard trigger let-off.
I very lightly polished the mating sear surfaces, then coated them with a light smear of Moly-G paste. I did not put any Moly-G on the pins. Just the sears.
I seldom use Moly-G, and the small cup of this I bought from Beeman 35-years ago has lasted a lifetime (barely 1% of it used).
But in this case, it helps tremendously. The trigger now breaks smoothly, with less felt pull (seems like half the pull from before). Guessing 10 oz. pull.
I don't like masquerading trigger design flaws with lubricants. But with all the other mods completed on this pistol, the trigger was the only thing holding it back. Now I think it will shoot predictably in a Field Target match.
Logged
www.DallasFTclub.org
_______________________________________
Bob D. - posts edited for style and typos - I can't help it, I'm an advertising/PR writer by profession (retired).
Motorhead
Field Target Shooter .... Stand em up Shoot em down
GTA Senior Contributor
Posts: 17753
2019 GTA Hall Of Fame Recipient
Real Name: Scott
Re: My MrodAir PP700 Field Target Pistol Development, to Date...
«
Reply #8 on:
April 14, 2016, 02:54:17 PM »
Yup ...
Tho do MOLY the pins. it will keep the wear on them & frame holes to a minimum.
Logged
Northern California ... Old Hangtown
**
Home of MOTORHEADS AG Tuning Services
**
* PM me for further contact & tuning info.
Sacramento Valley Field Target Club
#
https://sites.google.com/site/sacvalleyairgunclub/
Print
Pages: [
1
]
Go Up
« previous
next »
GTA
»
Target Shooting Matches, Discussion & Events
»
Field Target Gates
(Moderator:
Tpatner412
) »
My AirMax PP700 Field Target Pistol Development, to Date...