Initial Essential Upgrades for a pair of 1377's.

Jump to latest Follow Reply
Armstrong

Armstrong

Member
Nov 10, 2016
43
0
You'll have heard it all before.... but I can't find a thread in here that delivers the info I need.
Inadvertently I have a pair of 1377's stock basic coming in the mail. Well, living in Scotland , UK, that actually means in the mail to a registered Gun dealer where I then have a 90 mile round trip to go and identify myself as NOT being a terrorist with delusions of air guns having as much clout as a 45 calibre Rifle and collect them and bring them all the way home again.... God forbid I should ever have a gun secretly. (Sigh! :p )

That being done... I am fascinated to see the degree of customisation these things can enjoy.
I want a brass breech, brass muffler, full set of walnut woods, 14 inch barrel, brassy trigger, BUT WAIT..
These are the pretties.

I need to know what Guts need replacing to facilitate better breathing, better compression and escape and so on.
I need to learn.
And from the intensity of knowledge Ive seen in here so far I'm sure some pointers will appear.

My initial drive criteria are...
What initial items to I need to replace INSIDE the gun for superior (1) functionality (2) Longevity and (3) ease of use.

Many thanks and as a new user I'd like to say that the enthusiasm of this forum is clear to see and prompted me to join!

Armstrong.
 
Hi Pauly... Yes, I've scanned the world on issues regarding this Gun. Its a passion-project for me. But getting it right is something of a mismatch.
After replacing the breech, sight issues.
After replacing the trigger spring issues.
And I'm scratching my head because I need the sellers to say, OK, so you want THIS, then you'll also need THIS instead of what exists with it initially otherwise it wont fit.
And so on.

I feel I've come to the point where studies of the Practical will solve confusions with the Theoretical.
I can see what id like.
But I can't know from looking what IT would like
or what will fit afterwards
OR where to get it
OR if its the best thing to do.

So you see.......
There must be alotta guys n gals out there who've been here and know the directions. :) 


 
Upvote 0
There are some options depending on if you want to tinker on stock parts or buy a drop in.

Target gun: Reduced capacity flat top valve and flat top piston. These are efficiency mods, they will get you to the same velocity as 10 pumps on stock parts with 5 or 6 pumps. The reduced capacity valve will also reduce the top velocities that can be reached with more pumps. You can achieve similar result by modifying your stock valve and piston.

Hunting gun: High power flat top valve and flat top piston. Piston is same as above. The valve is heavily modified; increased capacity, enlarged and beveled exhaust port, sometime the poppet is replaced or modified as well. Larger valve exhaust also requires a larger transfer port and barrel inlet to match. You may also want an extended or fluted bolt probe. These modifications should get you around 12fpe with 20-25 pumps on a 14in barrel. Similar results can be achieved with modification of stock parts as well, stuffing the piston and modifying the valve, though the pumping efficiency will not be as good as the flat top combination.
 
Upvote 0
Hi Bill...
I thought about modifying some parts myself including the escape ports etc. but after looking at what's online now I prefer that option. Premade. At least hopefully parts are made with better precision tools than I have.

I like the idea of the High Power flat top valve and flat top piston. I think I've found a set where the valve exhaust is modified and the transfer port and barrel inlet are pre modified also.

Do you know where I could get a nice metal Breech top from please?

So, this is my shopping list so far.
""The Flat Man's Pack contains Pumper's Pack and the Flat Top Valve Kit.
  • So, the entire kit is the:
  • Power Hammer Spring (part of the Pumper's Pack)
  • Max Flow Exhaust Bushing (the other half of the Pumper's Pack)
  • Flat Top Valve
  • Flat Top Piston""
That's the first $90 spent. 

Barrels. Is a 14" or an 18" the superior option. $40 either way it seems.

A Gmac Black steel breech. $42

A brass extended probe with a recessed magnet at back. $19

A brass Barrel band where a longer barrel can be used. $30 

Brass safety bar. $10 

!!!!!!!!!!!!!!!! Adds up. 

Sights. I'm not really one for telescopic sights. I much prefer the rawness of an ordinary affair. Where can I find some nice sights for the 1377 please? They don't seem abundant.

Questions!

What exactly does a power adjuster do? Is it a power increaser? Because if it lowers the power what's the logical point. So I don't understand that.
and , do those prices seem right?

I'm just looking at a two stage trigger. I cant actually see what it means by "two stage" either. :(

And lastly, there are barrels on the market with as many as 3 grub screw fixings as opposed, I am led to believe, the single one from stock.
Is it an overkill? Or is this a beneficial issue?

If this is good preliminary Ill start to order the parts in the morning.

Thankyou again.
Neil.
 
Upvote 0
Hello Armstrong greetings
I have a 2289 same as 1377 only difference is caliber (.22) and detachable stock(although i don't use it.)
as well as a 1322 American classic and a list of other crosman products.
Answer your question about sights (I'll use the gmac web sight) the Gmac black breach your going to want the lpa MIM rear sight
http://www.gmaccustomparts.com/epages/BT3197.sf/en_GB/?ObjectPath=/Shops/BT3197/Products/2300-010
I have on my 1322 and its as nice as they come.
the other options are crosman Williams notched blade sight http://www.gmaccustomparts.com/epages/BT3197.sf/en_GB/?ObjectPath=/Shops/BT3197/Products/0066N
I had one i like it for its adjust-ability nice but didn't hang on to it lol
last would be the standard sight that comes with the gun meaning you would need http://www.gmaccustomparts.com/epages/BT3197.sf/en_GB/?ObjectPath=/Shops/BT3197/Products/001-0512
breach to mount it instead of the other that's about it for rear blade sights
a power adjuster does just that turn the screw and tensions the hammer spring there by increasing power it can be over done and increase wear on the spring. How long till it fails i don't no never had one fail yet lol
two stage is trigger is a trigger with two stages before it releases its popular on high end air rifles i have a Diana 34 with 2 stage trigger. English, German air rifles where first to have it but now seem like everyone has em or something like it. The advantage of a two stage trigger is knowing precisely when the trigger is going to break and cause the rifle to fire. As you squeeze back and apply pressure on a two stage trigger you progress through the first stage. It’s basically identical to a single stage at first. Then, instead of breaking and firing, you hit a “break wall” which is the stopping point between the first and second stages. Once at the break wall you apply a little pressure beyond what it took to get you that fire, and bang!
just put one on my 2289 made quite a difference much cleaner and less movement to the right caused by your finger pulling the trigger
Here's a pic of my 2289


 
Upvote 0
Hi Bhbeyes... That's a sweet looking 2289. :) You went Black on Chrome, I'm looking at Black on Brass with a wood set just like that. THAT is a delicious Woodset. :) I do like that.
Question.
Where the hell did you get a set like that because that is gorgeous. What I like about that design of wood is the way the stock meets across the top of the trigger to find the grips. Very nice bit of carpentry. I also like the hatching. If that is hatching. Either way the segmentation of the finish really works.

OK, what size barrel do you have on there. This is the one area I'm kind of stuck on. (My Girlfriends cracking snyde jokes here. hah!) Everything else is in the mail (including the guns) Pistons, flat top etc etc, ports, brass breech w. extended probe.... couple of external brass parts, some amber ash woods, brass grub screws, but the barrel. ?????????????????
Question.
Is the 18" an overkill. Seems excessive. 14 inch? Considering I'm trying to get as much power out of this as possible but at the same time keep it practical without having to go down the reinforcing avenue too far.... I would have said 14" is this a good estimation? Would it be enough fps increase considering everything else?

I like the 2300-010 LPA MIM Rear Sight. Nice and understated. I like that. I feel like if there are too many wheels and springs I look like the type who's gonna start flipping six adjusters every time a pigeon flies overhead to compensate for the air pressure waves its wings cause. :)
Understating is nice. Apart from the brassy wares everywhere else. So thanks for that.

Regarding the trigger. I've read about many people saying the two stage is a great advantage. I'll go down that avenue too. I found a nice complete unit "drop in". Brass trigger on black. So smart AND effective. 


ONE LAST QUESTION: Burrs! I saw an article that I cannot re-find about inserting internals.... flat top sets and such..... and it mentioned a de-burring suit BEFORE inclusion of upgrading the 1377's internals.
Is this an essential? Important? 
What "Burrs" am I looking at that will damage the new flat top suite on order? Is this just poor machining of the main body at the manufacture stage? Or results of removing "what was" in favour of "whats to be"?
What can I expect?

Thanks again for the information. Greatly appreciated. I'm learning fast. I've had a lot of firearms... and despite living out in the Scottish boonies with no neighbours to hack off with noise; closest neighbour a mile away; I still prefer the quieter firearms. So I'd like to make these real show pieces.
Armstrong.
 
Upvote 0
Yup that's the stock barrel foe 2289 14" as i recall i have a nice muzzle end piece but it makes it fell long really long lol
the grip set is a Steve Corcoran from http://www.woodsandwateroutdoors.com/crosman-grips
he's change the style since i ordered it though now it looks like two piece design now. sigh
it coast me 3 hundred usd to my door most expensive thing for my gun i ever bought lol
burrs the are created around the cut out for the pump arm sharp edges and the front hing pin hole when the pin is taken out it always leaves a burr run your finger on the inside of the pump tube (hinge pin area)you'll feel it.
here's a web page pic about it

check out http://www.airgunsmith.com he has a lot of info there i sure there's other sites but he comes to mind
hope I was some Help
 
Upvote 0
Thankyou for this Bhbeyes... I learn.
I'll watch out for the burrs.
Thanks for the link also. And I know about the costs. :p But if we weren't passionate about this it'd be something else. ;) It's either buy it, or learn how to do it yourself. Pends how many years we want o lay on the line to do that. Heh!

The postman's been so I need to go see.
Thanks again.
 
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu