What lubrication do you recommend for your air rifle?

[andrewM]

It seems there is no commonly agreed approach as to the lubrication of the piston/washer of an air rifle/pistol. Given this is a critical issue in terms of the performance, well-being, future and accuracy of any rifle, I thought I would commence a thread to see if we can reach a majority opinion, if not a consensus. That might be rather optimistic! On the other hand, discovering what others do and recommend, would be helpful to many readers and air-gunners.

As I see it, there is a difference of approach between leather and synthetic washers. I have therefore numbered the questions under varying categories.

1 Synthetic washers: it seems most people recommend SM50, which I gather is a mixture of oil and silicon. The advantage is that this substance claims to respond well to high temperatures and pressures.

Some people recommend an application of grease, such as LT2.

I am presuming (always dangerous to presume), that a mineral oil or neatsfoot is not recommended for synthetic washers.

2 Leather washers: it seems that neatsfoot or a mineral oil is advised. Is there a particular oil that can be regarded as the best? Some people use an SAE30 engine oil; others use neatsfoot. I have read, on the site, that some use 3 in 1 but I suspect this diesels rather more easily than other oils. Presumably, it is best to find an oil that operates under high temperatures and pressure, with a minimum of dieseling.

The above stated, when I bought my Original 45 in 1980, the gunsmith recommended SM50, which I used sparingly through the transfer port to lubricate the leather washer.

3 Neatsfoot: presumably, this is only for leather washers. Will there be adverse consequences if it is introduced where, previously, a mineral oil or SM50 was used and vice versa? Thus, does it mix ok with mineral oil and/or SM50?

4 Silicon oil: this seems to be a big 'no-no' for both leather and synthetic washers, for fear that it might migrate to other parts of the rifle and seize up the metal-to-metal working parts.

5 SM50: some claim that because it is a blend of oil and silicon, there is a danger that the silicon within could cause the same difficulties as per point 4, above.

6 Springs: it seems that LT2 is recommended sparingly. Is any oil recommended for the mainspring?

We therefore have plenty of technical questions here and if we were seeking to optimise the performance of our air rifles, how would these points be addressed?

I have omitted any reference to trigger lubrication, as it is a separate subject.

Rgds
A

[vbull]

I've only being rebuilding air rifles for a year or so as I got bored with firearms and therefore follow the advice given in the old Abbey Maintenance kits instructions, LT2 on new mainspring, Moly Paste on and off the piston head, SM50 on piston body. If there is still a twang from the mainspring on firing I will take apart again and put a heavier open gear Moly grease on the spring instead of the LT2. The instructions also say to put a few drops of Silicon Oil 35 into the compression chamber before reassembly but I don't due to all the stories you hear about this stuff. I've also found some Rocol Dry Slide which I buff on and off the cylinder walls but on my next gun I will be using fine graphite powder in the same way, buff on then off just to see if it performs as well as the Dry Slide. The last gun I did with a leather washer (Webley MK3) I soaked the new washer in Neatsfoot oil for a day after sizing it to the cylinder. I did however remove as much of the oil as possible before fitting by squeezing between kitchen roll. So far no problems. I'm also very interested to learn what others are using.

[Binners]

Been splashing it all over my guns for 50 years

didn't do me any harm

[Lakey]

The gunsmith at my local gun shop, where I was growing up, used to use a mixture of Vaseline and 3 in 1. That was in the days of 95% leather piston washers in spring guns (PCP's hadnt been invented then ), and he used to apply it with an old crows wing feather, out of an old baked bean tin.

I guess the Vaseline would have cut down on the dieseling properties of the oil on its own? And. the other main advantage was that it was cheap as chips

Happy days!

[Benelli B76]

On spring guns I use a thin smear of Halfords CV Lith-Moly grease on the piston and piston seal, and a thicker amount on the spring and spring guide.

Baz