When do you trim?

AK7AN

Beginner
Oct 30, 2015
191
8
I would like to trim my brass after I full length resize so I have a consistent length to start loading with. Only problem is that my trim pilot on my RCBS trim pro is to big and I have to use the next size smaller. Is this common or am I doing it backwards? BTW I am trimming Winchester 270 Win brass.
Take care
Ed
 
I always trim post full length resizing. Something does not seem right if your 270 cal pilot won't fit inside the neck of a resized case.
 
Brass tends to stretch after the first firing and I always trim after this stage. Check your pilot and make sure its a .270 pilot. It should fit your resized .270 brass.
 
I don't even use a pilot at all anymore.

Also, I won't trim until after first firing and then, I don't even trim them all, just the ones that need it.
 
Hunting ammunition? For bolt action rifles, I trim after the first firing and then only when brass has stretched at least 0.005 inches. For lever guns, I'm more fussy, trimming to uniform lengths with each firing.
 
I don't trim until they need it, even then I like to use the hand held LEE cutter/pilot trimmer in a drill. It cuts them back to the minimum, but have to add that all my rifles are hunting rifles and not Long Range Rifles at that. Different needs...
 
AK7AN":3t598wax said:
I would like to trim my brass after I full length resize so I have a consistent length to start loading with. Only problem is that my trim pilot on my RCBS trim pro is to big and I have to use the next size smaller. Is this common or am I doing it backwards? BTW I am trimming Winchester 270 Win brass.
Take care
Ed
I had the same problem once. It turned out that the button was not sizing the case mouth due to incorrect setup from my side. As far as I know, the pilots should fit the sized case. Kind Regards.

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Welcome aboard Kouros1. Glad to see you posting. Hope you join in the fun on a regular basis!
 
Please accept my apologies for not introducing myself. Is there an intro section?

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I would measure the expander ball in your die and compare to the pilot. The expander ball should open the resized neck, maybe it's undersized?
 
I don't trim until they are fired a couple of times , unless they are to long , then I only trim the long ones .new brass does not stabilize for the first few firings so I don't trim until the brass is fully formed . I don't use the trimmer pilot on my Lyman trimmer either . I also bought a couple of sinclair chamber length tools . I tend to let my brass get longer than sammi specs , since I know how long my chamber is by using these tools . hopefully I'll be able to test out the effects of different neck lengths at longer distances this summer .

can you load a bullet in the resized brass , or is the neck to small ?


http://www.sinclairintl.com/reloading-e ... 32925.aspx
 
Well I did some measuring and am still stumped. I measured the inside of the case necks and came up with .272 from the Lee full length die and .273 from the RCBS neck sizer die. The pilot marked with a "27" on my trim pro measures .275. I guess that explains why I can't use the 27 pilot on my trimmer.. :lol: I will continue to use the 25 pilot to trim my 270 brass. I usually don't trim until the brass goes over 2.54" and then trim it back to 2.53"
I did measure the 25 pilot and it measures .256, and my neck sized 257 brass measured .253 inside.. I see a trend here..
Thanks for all the great info and input.
Take care
Ed
 
It is supposed to be a tight fit. Have you tried cleaning the carbon out of the case necks and applying a trace of lube to the inside?
 
I have not tried lubing the case necks... The cases were clean as they had just come out of the tumbler and I clean them after that with a bore brush to get the media dust out.. I understand tight fit, but if the pilot is 3 to 4 thousandths bigger it won't fit. Its all good and I am all caught up on trimming cases for now.
I just need to get out and exercise more gun control.. (y) :grin:
Take care
Ed
 
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