The 13XX Cabin Fever Build

[Sh00ter]

Ed - my BuckRail order came today    I'll have to fab a pivot pin solution and have a couple options in mind, going to hit the hardware store later this week.  I'll need new screws for the B/R forearm and loose the OEM roll pins there while I'm at it.

My PA order is scheduled for tomorrow - breech and scope...

Dallas - What do you mean about parts shifting?  My gun seems tight - it's still brand new even though it's 10 years old - just came out of the box last week - not even broken in so there's that.  I know that OEM stuff can be sloppy at times but I'll inspect for defects and try pumping things up and see the differences.  I"ll definitely watch for the pivot egging out - I wasn't aware that is a thing but now I know.

The forearm from B&R is solid not skeletonized so I'm hoping a felt/velcro strip will help - I'll figure it out.

Thanks for those tips Friends - I'm sure other guns will come into play (replace the 760 from my youth, for instance).

Based on the lead time from MellonAir. I'll tear things down to put on the parts I have and get on with shooting some as best I can.  I'm just getting back into shooting in general and being able to get trigger time, even its just blowing air, is a good thing.

Be careful, when I got back into air guns I only had my old 880 on hand...then within 6 months to a year, I had about 20 more LOL...If I had a do-over, I would have gotten maybe less than 10, but it is a journey to learn what you like again.

[TheOtherSprocket]

Remember this thread?  Well, I finally built something after playing around with the gun above - see below.

Specs:
1322 Tube - Grey "Plasti-Dip" finish to try on the color
Steel breech
Mellon FTP pinned & 14" .177 barrel - I'll move to a .22 at some point.
Alchemy bolt & handle, SS screw set
Buck & Rail Plumper Pumper & AR type Minimalist stock
Bluefork Design trigger group with an Ergo grip I had on hand
TKO ldc 5"
Scope is unknown maker - 4x32 with mil dot reticle I had n hand - rings will change if I keep it, Leupold Rifleman 11MM base.

I came to this design set over the course of the months I've been here lurking learning and studying the mods of the 13XX platform.  The Bluefork was a splurge to be honest but it is a sweet trigger.

I'll be doing some chrony work to compare the stock, modded valve and FTP set.  Hoping this is as accurate as the above gun.

[gloob]

My issue with my 1322 was that parts would shift around while pumping, so even using a Lothar Walther barrel, my poi would shift around, thought the barrel it's self was capable of 1/3" groups at 25 yards easily.

No aftermarket slip/screw-on muzzle band will fix that. DIY is the way to go, here.

Soldered to the pump tube. Then the barrel slips in/out. And a brass wedge tapped into the slot seizes the barrel in place.

Drill, dremel, files, disc sander.

[Rick67]

My issue with my 1322 was that parts would shift around while pumping, so even using a Lothar Walther barrel, my poi would shift around, thought the barrel it's self was capable of 1/3" groups at 25 yards easily.

No aftermarket slip/screw-on muzzle band will fix that. DIY is the way to go, here.

Soldered to the pump tube. Then the barrel slips in/out. And a brass wedge tapped into the slot seizes the barrel in place.

Drill, dremel, files, disc sander.

My barrel is a free float.

Wish Blue Fork still made those bandless plugs.

It looked like Alliance Hobby's  "The Floater" but anodized:

[Rick67]

I had one CNC-made in stainless years ago:









The CAD drawing was supplied to me by Mr. John, aka JMJNC.

I remember paying around $25 for it, even if it was a one-of-a kind, but that was in Asia 

Here is another one:

[TheOtherSprocket]

UPDATE:
Once I got the correct screws for the trigger group (8-32 - 1/2") and put the thing back together, I decided to test it out.

The no-name scope pictured above was topped out for adjustment, leading me to believe that it wasn't a great choice.  I pulled a CP 4x32 off another gun that was known to be reliable.

My first group was a coupe inches low but dead nuts on for windage. So I turn up the dial - same thing - scope is maxed out for elevation adjustment.  So I put it down and thought about things.

I pulled the plastic barrel band and yes - it looks like the band is pulling the barrel down - causing the low hits.

Solutions:
Free-float the barrel - downside is that it can get knocked out of zero
a better barrel band - the inexpensive unit described recently in the bargain section comes to mind.
Drill out an OEM barrel band and see what I get for results.

Given the $$ I've dropped so far the metal band is winning out - even if I don't drill it for a grub screw it will limit the amount of deflection the barrel can move.

Any thoughts or experience with this would be appreciated.  I'm just glad my scopes aren't the issue.

[Rick67]

My issue with my 1322 was that parts would shift around while pumping, so even using a Lothar Walther barrel, my poi would shift around, thought the barrel it's self was capable of 1/3" groups at 25 yards easily.

No aftermarket slip/screw-on muzzle band will fix that. DIY is the way to go, here.

Soldered to the pump tube. Then the barrel slips in/out. And a brass wedge tapped into the slot seizes the barrel in place.

Drill, dremel, files, disc sander.

A floating standard barrel  (13xx OEM length ) can also be done solidly if you utilize one of those Disco silencer adapters with a half-moon belly from Serbia and Poland. The adapter melds with the contour of the pump tube and somehow locks the barrel in place. It's even tighter on a 22xx tube, of course, with its larger OD.

I also installed a free-floating 14.5" LW on mine with no change in POI (25 yards), but I did install multiple thin O-rings  on the barrel, so that it supports the added weight by creating a damper between the barrel and tube--- kinda like putting a bike tire interior cutout 2 to 3 inches from the receiver of a 10/22 to cheap-bed them standard whippy barrels.

[TheOtherSprocket]

To clarify, the barrel is 14" and not an OEM length - I'm not sure what adapter you're talking about but I'm guessing its for an OEM length barrel.  I'll see if I can find it.  Perhaps GMAC has one for reference?

The dampener makes sense to me though.

I'll be trying the metal band from ebay, what the heck.

Thanks

[Turbinator]

I'll be trying the metal band from ebay, what the heck.

Reviving this thread for a question --

I picked up a metal barrel band from eBay and now the stock Phase 2 forearm smacks into the barrel band and stops me from getting a full pump.

I can trim the stock plastic forearm to create enough clearance, but I'd rather keep the stock part intact.

Does anyone know if the Buck Rail Plumper Pumper allows for enough clearance to use with a metal barrel band?

Turby

[Spooner]

I'll be trying the metal band from ebay, what the heck.

Reviving this thread for a question --

I picked up a metal barrel band from eBay and now the stock Phase 2 forearm smacks into the barrel band and stops me from getting a full pump.

I can trim the stock plastic forearm to create enough clearance, but I'd rather keep the stock part intact.

Does anyone know if the Buck Rail Plumper Pumper allows for enough clearance to use with a metal barrel band?

Turby

If you are talking about the barrel band from Alchemy... you have to trim the forearm at the ends. I don't know about the plumper pumper but if it uses the same forearm design... most likely?

[Turbinator]

If you are talking about the barrel band from Alchemy... you have to trim the forearm at the ends. I don't know about the plumper pumper but if it uses the same forearm design... most likely?

Got it, thanks.  I bought a different barrel band but I suspect quite a few of these designs are the same, the barrel band and the stock Phase 2 forearm interfere with each other and require replacement or fitting.

Are there other forearm options out there that don't require trimming?

Turby

[TheOtherSprocket]

Turby - can you post a pic?  Something doesn't sound correct - I have a band on a PH2 gun with factory stock, no issues.

I suspect it's either your band or something else misaligned.  Also - I have a set of OEM brown stocks you can have for shipping.

[Spooner]

If you are talking about the barrel band from Alchemy... you have to trim the forearm at the ends. I don't know about the plumper pumper but if it uses the same forearm design... most likely?

Got it, thanks.  I bought a different barrel band but I suspect quite a few of these designs are the same, the barrel band and the stock Phase 2 forearm interfere with each other and require replacement or fitting.

Are there other forearm options out there that don't require trimming?

Turby

I would like to see a pic of the one you bought as well. if the front face of it goes straight down and squares off like this one...
https://www.ebay.com/itm/303499445877?hash=item46a9fa0675:g:MJcAAOSwQj9eVZOB&amdata=enc%3AAQAHAAAAoMGh0SnJqVEQVBzvW4pCnot98zSYlVxrxxJepa%2FzvvBQb0O69X3Uqgto0R%2Blg59c70qPmhlPO2p90GVIz7qMNf6O%2FMh5marJXQ0oAzrqIea4%2BdoVjzBZwAryCBW6W6IV5TCWHKAeET63K5pTBUZIt5WuoTb%2FcdtnZSzjBCpc6QuBGYGzzxsNxKY7RzwkfIcTYp%2FALNYLptLnT57ujtI4a4o%3D%7Ctkp%3ABk9SR6ry05PcYA
... trimming is necessary. I have one of these from him but without the integrated sight.

These are what I prefer and in my opinion... the best design out there. They are not cheap, but well worth the price...
https://maverickcustomairguns.com/product/crosman-1377-1322-pass-through-barrel-band/
no trimming necessary, has a set screw, worked perfectly with my plastic forearm as well as my Tom West custom stock/forearm set.

[Turbinator]

Here we go gents, 2 pics to show the issue:


Above: The barrel band is just ever so slightly more "pronounced" than the factory one, or even the Buck Rail one.  It sticks out forward past the muzzle of the gun just enough to interfere with a full swing of the pump forearm.  Stock Phase 2 plastic forearm shown.  (Please ignore my janky screw front sight post for now...)


Above: Because of the interference, the pump cup can't extend out far enough to get a good pull of air to compress.

The easy solution is to just get out a saw and cut off enough of the front of the stock forearm to allow for a full swing of the pump arm.  At least, that's how I see it...

Thanks guys for looking!

Turby

[Turbinator]

Ok... update...  Probably as most of you are, I'm an obsessive tinkerer.  This really isn't a hard problem to solve.  Give a guy a hammer, a Dremel, and anything can be accomplished:



The pump arm, with the stock Phase 2 plastic forearm, now gets full pumps each time it's pumped.  Yay!  Time to go test!

Turby

[TheOtherSprocket]

Thanks for the pics - I'll have to check mine now.  I've got a couple from a mfgr in China and a couple from Germany - I'll have to check the clearances on each now.

[Turbinator]

Thanks for the pics - I'll have to check mine now.  I've got a couple from a mfgr in China and a couple from Germany - I'll have to check the clearances on each now.

Nice!  I actually bought the German one!  It arrived this past week.  That's the one shown installed on my 1377 there.

Turby

[Spooner]

Looks good Turby. 

[Turbinator]

Looks good Turby. 

Thanks!

My next problem is there is a bit of air leakage around either the transfer port, or the bolt probe.  Going to troubleshoot.  I already o-ring'ed up the transfer port nice and tight, so I'm going to focus on the bolt probe next.  I think it needs a new o-ring.

I read someone say the bolt probe o-ring is 003, but I have 003 and they don't fit.  I think 005 might be the right size for .177.  I just ordered some and they should arrive by the end of this coming week.

ETA: I think the transfer port might still be the problem.  I see a streak of oil coming out from that area.  Maybe it's time to ditch the plastic.

Turby

[Rick67]

I have relieved a cheapo disposable lighter of a very small and thin O-ring that fits the .177 probe slot.

The said O-ring is to be put behind the OEM one.

It fits so snug that when you shift the cocking bolt to its locked position it stays  satisfyingly secure with obvious tension.

Unfortunately, not all disposable lighters contain these O-rings, but they were very common in those very cheap translucent lighters in Asia--- like $0.030 cheap, no kidding.

I used to have a bunch of them in Asia 'cuz I would pick thrown lighters and smash them for their offal.