Remain crimped brass, how much do I take off?

[AKM]

i bought a small/large reamer from hornady for crimped cases, how much material do I remove? I've only done two to try them out but it seems like it takes a lot.

I don't have primers right now to test out the pockets.

Pictures two reamed and two untouched.

Also stupid autocorrect on the title haha

 

[grasshopperglock]

The second from the right looks like what the reamer should remove. I have to remove the primer crimps too. GGG NATO cases. The reamer makes a pretty big funnel but the material removed is from the thickest section of the case. When they press the crimp it also shrinks the primer seat snug against the primer. The 'crush' needs to be removed too or the primer will be a pain to start. Or gets bent. You'll see small shavings of brass from where the primer actually shaves from the primer seat edges.

With the big funnel from the reamer. The primers are super easy to seat. No shavings. I use a hand primer.

Don't forget to deburr the flash hole on the inside.

 

[robertc1024]

Holy crap! That one second from the right is way more than I'd do. When hand trimming, I just go enough to trim off the crimp. You can feel when it does because turning the reader gets smooth. I gave up on that and use an RCBS primer pocket swager. Way faster and more consistent.

 

[grasshopperglock]

On the reamer picture.

Run it down until the tip of bit starts to rub against the bottom of the primer seat. Whatever funnel it makes at that point is correct.


Btw,

The threads on the reamer is the same as an archery arrow insert. If you screw one on the reamer threads. You can chuck it in a cordless drill. Then it go's quick. Smoother with less to none bit chatter marks. Hold the casing with a glove. They get hot. Cuts a better edge with little to no chatter marks. After doing a hundred cases, you'll be a pro at it. Forget that hand reaming stuff.

One of these. They're a few bucks for a pack. Wally world has them. Take the reamer with you and check the thread size of the insert. They have a couple of sizes.

 

[AKM]

The second from the right looks like what the reamer should remove. I have to remove the primer crimps too. GGG NATO cases. The reamer makes a pretty big funnel but the material removed is from the thickest section of the case. When they press the crimp it also shrinks the primer seat snug against the primer. The 'crush' needs to be removed too or the primer will be a pain to start. Or gets bent. You'll see small shavings of brass from where the primer actually shaves from the primer seat edges.

With the big funnel from the reamer. The primers are super easy to seat. No shavings. I use a hand primer.

Don't forget to deburr the flash hole on the inside.

I've only really seen swaged brass before I would have thought this was taking off way too much material. I need a set of calipers so I can measure the pockets.

 

[orbitup]

You aren't going to get good measurements on primer pockets with calipers. You need them for other stuff though. Just a touch with the reamer is all you need. If you really want to check them get these.

https://www.brownells.com/aspx/search/productdetail.aspx?sid=150244&pid=71030

 

[AKM]

Went to chuck the bit in my drill and the chuck is froze up, and I busted teeth in the gear box trying to free it, great haha

 

[AKM]

Much better, I assumed before the tool was supposed to bottom out. Bad idea.

 

[Charley]

I use a primer pocket uniformer tool mounted on a prep center. Works well, and much faster than a swaging tool. Only takes a couple of seconds per case.

 

[avvidclif]

Much better, I assumed before the tool was supposed to bottom out. Bad idea.

That's more like it.

 

[Dawico]

On the reamer picture.

Run it down until the tip of bit starts to rub against the bottom of the primer seat. Whatever funnel it makes at that point is correct.


Btw,

The threads on the reamer is the same as an archery arrow insert. If you screw one on the reamer threads. You can chuck it in a cordless drill. Then it go's quick. Smoother with less to none bit chatter marks. Hold the casing with a glove. They get hot. Cuts a better edge with little to no chatter marks. After doing a hundred cases, you'll be a pro at it. Forget that hand reaming stuff.

One of these. They're a few bucks for a pack. Wally world has them. Take the reamer with you and check the thread size of the insert. They have a couple of sizes.

View attachment 139420

You can just chuck the reamer right into your drill too. Either the threaded part or the fatter part behind the cutter if you don't want to damage the threads.

 

[AKM]

You can just chuck the reamer right into your drill too. Either the threaded part or the fatter part behind the cutter if you don't want to damage the threads.

Yeah I was going to do that but my drill chuck took a dump on me.

 

[grasshopperglock]

You can just chuck the reamer right into your drill too. Either the threaded part or the fatter part behind the cutter if you don't want to damage the threads.

If I had no more then 5 cases to trim the crimp. I'd still use a drill. I bought a RCBS reamer head from Gander before they closed. Didn't spend money on the handle. I had to cut more then a hundred cases. I couldn't imagine doing it by hand with a screwdriver handle. I recognised the threads from having archery stuff. I hold the cases with a piece of split leather. Then stick them to the reamer. Drill speed isn't high. Medium low. Fast enough to cut it but not fast enough I couldn't hold the case still.

Once I got into groove removing the crimps. I'm guessing I could do about 2-3 cases a minute. No rushing with a nice clean cut.

 

[LOCKHART]

Great big second on the RCBS primer pocket swaging die. It is absolutely the fastest way to remove military brass primer crimps. Back in '74, I was making LOTS of .44 & .357 Automag brass from military 7.62 NATO brass. It is the quickest and most uniform method. And you are not cutting away any brass.

 

[ScS]

A good size 3rd on RCBS. Has a shoulder for a stop, can't go wrong