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Minimizing case trimming

Any secrets? Seems like I hafta trim case necks alot in my semi guns.....more than my bolt guns. I'm not loading especially hot, I shoulder bump and anneal.

What case trimmer you recommend when you gotta trim alot of cases? The Henderson PrecisionGen 3 looks good, but pricey.
 
Any secrets? Seems like I hafta trim case necks alot in my semi guns.....more than my bolt guns. I'm not loading especially hot, I shoulder bump and anneal.

What case trimmer you recommend when you gotta trim alot of cases? The Henderson PrecisionGen 3 looks good, but pricey.
Number 1.....just the nature of semi-auto's and annealing is not helping your problem because annealing softens the brass. When the rifle is fired,the cartridge is pushed forward and the pressure expands the forward part and seizes the chamber...the bolt/extractor pulls on the body while the cartridge case is pressured up against the chamber thereby stretching the cartridge case body. Moderate loads is about all you can do to minimize this.
 
I only shoot bolt rifles, and I am not sure about this, but I don't see why it wouldn't work - using the Sinclair chamber length gauge. I've reduced my trimming to well over 50% even applying Sinclair safety factor by measuring the chamber length of all my rifles. With few exceptions, the chambers are much longer than SAMMI specs listed in reloading manuals.

Those with semi-autos, please chime in if you know if this gauge work for semi-autos.
 
Wilson with the micrometer adjustment. There is a driver available for a drill.
Yeah, the drill helps a lot, there's still a lot of time putting each case into and out of the case holder.

This works great and is fast. When I first got it I timed myself, did 100 300wsm brass in 17 minutes. I wasn't racing just going steady.
That 17 minutes includes chamfering and deburring?
 
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Number 1.....just the nature of semi-auto's and annealing is not helping your problem because annealing softens the brass. When the rifle is fired,the cartridge is pushed forward and the pressure expands the forward part and seizes the chamber...the bolt/extractor pulls on the body while the cartridge case is pressured up against the chamber thereby stretching the cartridge case body. Moderate loads is about all you can do to minimize this.


That makes sense....softened cases stretch more. Thanx for the suggestion re: moderate loads. Just trimmed my brass. I'll check how much it stretches per firing.
 
Any secrets? Seems like I hafta trim case necks alot in my semi guns.....more than my bolt guns. I'm not loading especially hot, I shoulder bump and anneal.

What case trimmer you recommend when you gotta trim alot of cases? The Henderson PrecisionGen 3 looks good, but pricey.
Have you considered an X Die? trim once and use the X to not trim again supposedly, I have a new unused 30-06 and a 223 die from RCBS but they still sitting in the cabinet. Idea is to not have to trim again using the X Dies. But I digress.
As to trimmers I use a Giraud
 
Wilson with the micrometer adjustment. There is a driver available for a drill.
Just thinking about it. Does the case body get stretched longer making it look like the neck got longer? After firing how much does a bump gauge tell you the case body got longer compared to OAL change. I'm not OCD but I look at a few things that are simple and easy to do. I don't think if a bump gauge can tell you if the body got longer or just the shoulder shape changed.
 
Just thinking about it. Does the case body get stretched longer making it look like the neck got longer? After firing how much does a bump gauge tell you the case body got longer compared to OAL change. I'm not OCD but I look at a few things that are simple and easy to do. I don't think if a bump gauge can tell you if the body got longer or just the shoulder shape changed.
I think you would find some of both on initial firing new brass.
 

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