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JeepHammer · August 22, 2016, 01:33 PM

Depends on your case sizing abilities.
'Trim It' is about like all the other flat faced cutters on the market,
You still have to champfer inside and usually outside once the mouth is cut to length.

The 'Trim It II' has a 'V' shaped cutter that trims to length, champfers/Deburrs in one step.

The reason I say it depends on your resizing capabilities is the 'Trim It' is a datum point index, datum point being on the neck down shoulder.

Head Space is determined from datum point on the shoulder to the head stamp end of the case.
If the head space is correct, and dead on, then the cutter will index off the shoulder/datum point and give you VERY accurate cuts since its almost infinately adjustable.

The 'Got Ya' here is stuff like 'Spring Back' of different brands of cases, or different hardness of cases that don't all headspace size exactly the same...
If the sizing die gives you (+/-) 0.002" or 0.003" difference in cases, that's going to carry over into the necks since the datum point on the shoulder isn't in exactly the correct spot.

Personally, I use the crap out of my 'Trim-It II' and its the closest thing to exact I've found yet without hand lapping the cases...
When aim processing cases I double size die in a progressive machine, meaning I run through two sizing dies,
One to decap and NOT squeeze the neck, get the shoulder back where it belongs,
The next die finalizes the shoulder/headspace, supports the shoulder while the neck gets sized.
VERY accurate headspaced cases this way, so the trimmer works exceptionally well...
(Some people 'Double Tap' the body of the case in a single die before pulling the sizer ball through the neck,
But this leaves the shoulder unsupported in a common die)

Anyway, its up to you,
One tip, you *Might* consider honing out the neck of the die so it doesn't undersized and work harden the neck,
Only push the brass back where it will be 'Gently' sized by the sizer ball,
This keeps the crush, opening by the sizer ball from moving your shoulder around in common dies and gives you more accurate headspacing with common dies...

August 22, 2016, 01:33 PM	#2
JeepHammer Junior member Join Date: February 27, 2015 Posts: 1,768	Depends on your case sizing abilities. 'Trim It' is about like all the other flat faced cutters on the market, You still have to champfer inside and usually outside once the mouth is cut to length. The 'Trim It II' has a 'V' shaped cutter that trims to length, champfers/Deburrs in one step. The reason I say it depends on your resizing capabilities is the 'Trim It' is a datum point index, datum point being on the neck down shoulder. Head Space is determined from datum point on the shoulder to the head stamp end of the case. If the head space is correct, and dead on, then the cutter will index off the shoulder/datum point and give you VERY accurate cuts since its almost infinately adjustable. The 'Got Ya' here is stuff like 'Spring Back' of different brands of cases, or different hardness of cases that don't all headspace size exactly the same... If the sizing die gives you (+/-) 0.002" or 0.003" difference in cases, that's going to carry over into the necks since the datum point on the shoulder isn't in exactly the correct spot. Personally, I use the crap out of my 'Trim-It II' and its the closest thing to exact I've found yet without hand lapping the cases... When aim processing cases I double size die in a progressive machine, meaning I run through two sizing dies, One to decap and NOT squeeze the neck, get the shoulder back where it belongs, The next die finalizes the shoulder/headspace, supports the shoulder while the neck gets sized. VERY accurate headspaced cases this way, so the trimmer works exceptionally well... (Some people 'Double Tap' the body of the case in a single die before pulling the sizer ball through the neck, But this leaves the shoulder unsupported in a common die) Anyway, its up to you, One tip, you Might consider honing out the neck of the die so it doesn't undersized and work harden the neck, Only push the brass back where it will be 'Gently' sized by the sizer ball, This keeps the crush, opening by the sizer ball from moving your shoulder around in common dies and gives you more accurate headspacing with common dies...