Recommendations for a Diana 27...

[Toxylon]

I have never understood the silicone oil recommendation for leather-sealed guns. Silicone oil is a galling killer on metal-on-metal contact, and I just don't see how you can control the silicone oil, in lubing amounts in the compression chamber, to not migrate onto metal/metal interfaces: the stuff shoots out from the transfer port as an aerosol with each shot.

That being said, I use only neat's foot oil, and have yet to see a reason to change. It's an actual leather conditioner / revitalizer, and it plain works, with zero risk. I also get a small kick out of it being an ancient lube, so much at home with guns from days gone by.

Lithium grease would be my second choice, but I have no personal experience with it.

[Razor62]

I 2nd the neatsfoot oil for leather seals. It works. It's always been the go to for leather.

[tjk]

NeatsFoot oil worked for me in rebuilding an old leather sealed Chinese underlever. As far as scopes go, with a light recoiling gun like the Diana 27, you might get lucky with a cheap little  1/2' .22 RF scope.

[Kragman1]

Thanks again everyone!

I'll get my hands on some and put it to good use.

I also dug out a feathery light Columbia (yep, the sportswear people) 4x32 scope for the rifle and mounted it tonight.
Published specs say that it weighs 8oz, I'd say that it weighs no more than that - maybe less.  I really like the glass and turrets, and I'm hoping that it holds up on a rifle in the 5-6 fpe range like my 27.  If not, I will have smoked a nice little rimfire scopehope to try it soon.

Wish me luck!

[MDriskill]

BTW, I happily appreciate that these rifles have a very modest power level (and all the good manners that comes with it) but I do wonder how a modern seal would do in one. 
If it turns out that mine needs a piston seal, I have no idea if I would be better staying with leather or converting.

Several years ago I had a friend who did the "Full Monty" on a model 27. Professionally sized aftermarket synthetic piston seal...Sunnen honed chamber for perfect concentricity...polished Maccari spring...high-tech lubes...other stuff I'm forgetting. When he got done, guess what - it made EXACTLY the same power as before he started! He was pretty annoyed and I tried hard not to laugh where he could see me! 

Diana's designers knew what they were doing, and I'd add that the piston seal and mainspring in these guns are really top quality. I have a 1980 model 27 that has never been apart and still shoots the same velocity as when I got it nearly 30 years ago. Over the years it has "tuned itself" into that nice crisp "chonk!" that you like to hear when shooting a springer, too.

[MDriskill]

I have never understood the silicone oil recommendation for leather-sealed guns. Silicone oil is a galling killer on metal-on-metal contact, and I just don't see how you can control the silicone oil, in lubing amounts in the compression chamber, to not migrate onto metal/metal interfaces: the stuff shoots out from the transfer port as an aerosol with each shot.

That being said, I use only neat's foot oil, and have yet to see a reason to change. It's an actual leather conditioner / revitalizer, and it plain works, with zero risk. I also get a small kick out of it being an ancient lube, so much at home with guns from days gone by.

Lithium grease would be my second choice, but I have no personal experience with it.

Very interesting comments. I do use silicone oil, but definitely agree you have to be very careful with it. I thoroughly soak the seal, but then leave it standing on a paper towel overnight to pull out all excess loose liquid. It is an excellent preservative and leather-to-metal lube, but a downright dangerous metal-to-metal lube.

All that being said, I'm gonna try neatsfoot on the next one! Be aware that it comes in different quality grades, though. Buy stuff labeled "100% pure neatsfoot oil." Others are compounds that may contain petroleum oil or other things you don't want in your airgun.

Another interesting lube I'd like to try is Abbey SM 50, which is oxydized castor oil with some moly powder added (rumor has it that Beeman's "Ultra Lube" was nothing but re-packaged SM 50). And castor oil is another tried and true vintage lube, used in WWI aircraft engines and other applications. Have had trouble finding the stuff for sale in the US though...

[Methuselah]

Thanks again everyone!

I'll get my hands on some and put it to good use.

I also dug out a feathery light Columbia (yep, the sportswear people) 4x32 scope for the rifle and mounted it tonight.
Published specs say that it weighs 8oz, I'd say that it weighs no more than that - maybe less.  I really like the glass and turrets, and I'm hoping that it holds up on a rifle in the 5-6 fpe range like my 27.  If not, I will have smoked a nice little rimfire scopehope to try it soon.

Wish me luck!

I saw one person here posting they put a Leupold M8 4X on his air rifle. Not an AO either, and I recall thinking, now that's class!

[Kragman1]

Ha!  I have a Leupold 6X that's so tempting.
I may send it to them for a service and ask for the parallax to be set to 35 yards.
That would be a really nice set up for a light springer!

The little Columbia is a big risk on any springer, I think.  But the 27 is only a 6 or so fpe gun, so...  fingers crossed....