1389 Backpacker restoration - Finally finished - long post (sorry)

[Stinger177]

Back in the early '90's when I bought my Beeman/Webley Tempest, I also bought my son a 1389 Backpacker - serial # tells me it was made in March of 1990. After all these years later with several moves, my son growing up and successfully on his own, etc., the Backpacker was still around. I retrieved it from my son about a month ago to see what I could do with it after having just recently modded my own (garage-sale-new-to-me) 1377. The Backpacker was in the sort of shape one might expect of something cared about, but not like jewelry. It was missing the original green rear stock and grips but other than that was in pretty good shape.

First thing I did was just put in new seals. First shot on ten pumps was 496fps with RWS 7.0g wadcutters. This after 28yrs! Since then I've put on a 14" rifled barrel (that I cut and "crowned" myself), better trigger blade (MagnumAir), polished Supersear (the original without the hardened pins - needed a slight reshaping for the 1389), lightened sear spring with nylon insert, FT piston and valve from Mellon-Air, TKO and a new rear stock. Scope is one of those Kruger non-branded deals from Ebay 3-9x40AO (actually nicer than my UTG version of the same), scope covers from Cabela's. It had the old original Tasco scope on it that cleared the rounded-top breech. I had to mill the bottom of the new scope rings to clear that rounded top.

Just finished it today and now getting: 6 pumps-486fps, 8 pumps-542, 10 - 605, 15 - 662, 20 pumps yields 705fps.

These numbers compare almost identically to my similarly modded 1377 (see pic below).

Amazingly, (and as evidenced by the numbers above) the original pellet/breech insert ring is in perfect condition.

I also bought a new black forearm and cocking link, but the Fatty is so much better I left it on...my son can change it if he wants.

My intent on this resto was not to get an overall increase in fps, just to get to about 500 match-speed for target shooting and with fewer pumps required to do so. The fact that it will get to 600 or even 700 is an added bonus (if one wants to really go 20 pumps). Was hoping that 3-4 pumps would make the 500 mark, but 6 is still better than 10, eh?

My son has no idea what he is getting back, only that I am fixing it up to shoot again. I honestly don't want to give it back, but, he is my son, and I already have something similar. The flip over breech loading is really easy to use. You can do the whole shot cycle without having to un-grip your right hand.

This thing is as accurate as anything I own, except maybe the 46M. New rifled barrel helps, the old one is smooth bore. Ten-shot dime size holes at 10m are easy.

I really wish that Crosman still made this model. The whole shooting cycle seems so much smoother. It's also nice to be able to pump it up, load the pellet, walk around and then cock when your ready to shoot.

Pics below are the 1377 (upper), 1389 (lower)

So, anyway, I'm so happy about it I wanted to share it with someone.

Thanks for letting me share.
I'm off to my Crosman modification therapy meeting.

Stinger

[CraigH]

They look nice, Dennis!         Nothing like having expectations met for a happy ending.    Getting the number of pumps down with the same velocity is a welcome result.   I always forget about the different breech design of the Backpacker.

Multi-stroke-pneumatics are altitude sensitive since the air is less dense.   My 1322C with FTP has an increased valve volume.   That was probably a mistake - it takes a lot of pumps, but makes good power for my altitude of 5835 foot elevation.   I think it would be better with unmodified valve

[Stinger177]

Thanks Craig. I put a lot of heart into this rebuild. Nice to see that someone else appreciates what these 1389's are.

Thanks for the heads up on altitude. I should have thought of that. So, is 705 pretty good, even on 20 pumps?

[CraigH]

Here are a couple of webpages about airguns and altitude - and which powerplants are most affected.

https://www.pyramydair.com/blog/2008/02/shooting-airguns-at-altitude/

http://bestairriflereview.net/dealing-with-high-altitude-shooting/

There are GTA topics also - try searching "air gun altitude".