Lubing liners and cleaning cases

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Handeman

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There are several schools of thought about what lube to use on o-rings, whether you should lube the outside of the liners, etc.

I only lube the o-rings, never lube the liners. I have no problems with the liners coming out of the cases. Attached are a couple of photos of how the internals came out of the cases for me today. Both are Hobbyline, one a 24/40 F12J and the other a 29/40-120 G64W. I've also had a 54/1706 K695R come out the same way, along with a number of other 29mm & 38mm HPR Aerotech loads.

The nozzle, liner, ejection charge, all come out of the case as a single piece. There is more to clean off the outside of the forward closure/ejection well, then from the inside of the casing.

IMG_0231.jpg

IMG_0229.jpg
 
When Im not running a self-cleaning propellant thats the way I do it. Only the Orings get lube. I do slather some on the nozzle/carrier sides to ease insertion, but none on the liner. Works through 4.5" for me so far.

Ben
 
I always put a light coat of grease on the outside of my 29/40-120 liners. Clean-up seems to be easier than before I started this practice, but it could just be me.
 
I have always lubed my liners. I believe the biggest reason for doing so is that it removes any gaps from between the liner and the casing. These gaps can cause liners to crack exposing the casing to the very hot gases possibly causing a burn through in the case. Plus it seems the liner slips out easier during cleanup.

Just my thoughts.
 
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I have always lubed my liners. I believe the biggest reason for doing so is that it removes any gaps from between the liner and the casing. These gaps can cause liners to crack exposing the casing to the very hot gases possibly causing a burn through in the case. Plus it seems the liner slips out easier during cleanup.

Just my thoughts.

I've never lubed my liners and they seem to slip out just fine during cleanup. I've had a lot (most) liners crack, but I've never had a case that was affected by it. Cleaning the gunk from the area where the crack was tends to take a little more elbow grease, but the cases have never been damaged. Not sure how much cleaning is required when the case is lined with burned/melted grease.
 
Lube can act as a glue and make taking the liner out a pain. Other times it makes it easier to come out. An unlubed liner should be able to come out easily enough.
 
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