Thread: Pressure sign in the single shot

Was out developing a load for the bergara the other day(unsuccessfully, turns out you need the pic rail screws to be tight to shoot good groups) when it occurred to me that I didn't actually know what to look for in pressure signs. My primary indicator has always been ejector flowi/swipes.

I assume you just have to go entirely off primer flattening and cratering? Primary extraction is pretty strong due to the massive lever so hard to detect hard extraction. Anything obvious I am missing?

Load were 168 nbts over H335 in winny brass. 42.5 shows some flattening and a minor crator. This sound abiut right?

I reckon you are on to it....primers/low brass life/hard to extract would be all you can go by. size them as long as chamber will allow and brass life SHOULD be good. assumption is the mother of all fuckups....if you are loading a 7.62x39mm that load will be really hot...if loading the mighty dirty06 it will be under loaded.... .308winchester perhaps???

Got a decent Chronograph ?

Ive had the rail come loose twice so much ammo wasted so frustrating.
I locktite the shit out of everything with the stuff we use on motors now
Probably couldnt get them off if a wanted to.

Originally Posted by muka88

Ive had the rail come loose twice so much ammo wasted so frustrating.
I locktite the shit out of everything with the stuff we use on motors now
Probably couldnt get them off if a wanted to.

Had the same issue with my bergara single, was driving me nuts trying to get it zeroed.
Loctite sorted it

You would not believe the number of firearms I've brought off TM, etc, worked on that the scope mounts are only screwed on (good old Gunshops ) no loctite etc & are loose

You can clearly see where the mount has been moving around, time & time again

Originally Posted by Kiwi Greg

You would not believe the number of firearms I've brought off TM, etc, worked on that the scope mounts are only screwed on (good old Gunshops ) no loctite etc & are loose

You can clearly see where the mount has been moving around, time & time again

i bet the blokes that sold you those guns thought they were dropping a 4 moa lemon on you haha

Originally Posted by veitnamcam

Got a decent Chronograph ?

Nah I should really invest in one. Might be a good use for my Cindy bucks

Originally Posted by muka88

Ive had the rail come loose twice so much ammo wasted so frustrating.
I locktite the shit out of everything with the stuff we use on motors now
Probably couldnt get them off if a wanted to.

Yup rail is now 'glued the fuck on' for want of a better term

Depends on the sort of single shot action. Falling block like Ruger No1 will be different to say a Blaser K95. Big thing to remember with some you don't have the primary extraction like a bolt action, when you get expansion.
And trust me I found out this the hard way with my No1, in typical windy/dusty nor west conditions in the Mackenzie - dust in the chamber/action don't work well.

I found that in the example of a small Martini (224 Hornet chambering) the brass case would stretch if the load was an overload. So, fire a sequence of incrementally increasing loads and measure the case length before and after the shot with a set of calipers (remove the primer or the measurement will be inaccurate). The load that could be fired several times without stretching the case was the correct maximum load for that cartridge/rifle combination. Cases are going to stretch to some extent in what is effectively a rear-locking action. I wanted the Hornet cases to last at least 20 reloadings. So, I found the load that would consistently produce at least 20 loads per case. So, decide how many times you want to be able to load each case and work from there. Measuring the increments of stretch in the length of a brass case is a very easy way of knowing the limits on a single shot rifle.