9mm flat point seating variance?

[thefish]

Decided to load up some 9mm this afternoon. First time seating xtreme flat points, as I've always used the round nose.

Loading manual says oal should be 1.070".

Strange thing is that when I seat the bullet, without adjusting the die at all, I get between 1.080" and 1.050".

Using round nose bullets, the oal has always been dead on.

Is there a reason for this, and more importantly, is 1.050" oal ok?

Bullets plunk fine at 1.070" in the shield.

Tia.

 

[Skinnedknuckles]

It seems you are using the same seating die you used with round nose bullets. You don't mention whether it is a RNFP or TCFP, but I would guess it is the TCFP nose shape. Your seating die that worked so well with RN bullets will not efficiently straighten and seat a TC bullet, resulting in varying OAL. You would be better off making or investing in a seating die designed for the flat nose bullet shape.

 

[thefish]

That's a good question. I
It's these.
http://www.xtremebullets.com/9mm-124-FP-p/xc9mm-124fp-b0500.htm

I would think they would be round nose flat point?

I was unaware there are different dies, but that makes sense.

The oal data I'm using is from the accurate load data for no7 using RAN FP 124 grain.

 

[LiveLife]

Using rounded bullet seating stem with flat pointed bullet won't produce ideal results.

If you are using Lee dies, they provide a service for custom seating stem for $8 - http://leeprecision.com/custom-bullet-seating-plug.html

The Bullet Seater Plug that comes with the die set is as close to generic as we can make it. If you find that the bullet seater plug deforms the nose of the bullet you are trying to seat, we can make a custom bullet seater plug to fit your bullet. For this we would need a sample bullet, payment of $8 plus shipping. Current lead time is 4 to 6 weeks.

Please send sample bullet and your invoice/order ID to:

Lee Precision, Inc.
4275 Highway "U"
Hartford, WI 53027

 

[moxie]

Ditto what bds said.

You don't need a different die. Just a different seater plug (stem). FYI, RCBS die sets come with two stems. One for round, one for flat.

 

[thefish]

Thanks guys, it's a lee die. I'll give them a shout.

I have a few with oal of 1.050 to 1.065.
Are those ok to shoot or should I pull them?

Accurate no7 loaded mid level at 6.5 grains.

 

[GJSchulze]

That looks very much like my Precision Delta FMJ-TC. Note that the sides between the top and the shaft are flat and not curved. I've always wondered what the difference is between that and a RNFP. Is it that the sides are curved vs. flat?

With my Hornady seater die I get about a .015 spread. .3 seems a bit much.

But really, unless you are close to max load it should still be safe. If you're at max load then a reduction in the OAL could result in high pressure.

 

[Skinnedknuckles]

That's a good question. I
It's these.
http://www.xtremebullets.com/9mm-124-FP-p/xc9mm-124fp-b0500.htm

I would think they would be round nose flat point?

I was unaware there are different dies, but that makes sense.

The oal data I'm using is from the accurate load data for no7 using RAN FP 124 grain.

To see the difference between the truncated cone flat point and the round nose flat point, look on the X-treme web site for your bullet and the slightly heavier http://www.xtremebullets.com/9mm-135-RNFP-p/xc9mm-135rnfp-b0250.htm.

Lee does offer a very inexpensive service for special seating plugs, but I'm lazy, impatient, and cheap so instead of sending them every bullet I wanted a plug for, I ordered several standard plugs in each caliber I load and make my own. I published the process at http://www.taurusarmed.net/forums/reloads/126434-bullet-seating-plugs.html and it is very simple to do. This way, when I decide to try a new bullet, if one of my plugs isn't a good fit, I can have a custom plug ready for loading by the next day (let the epoxy harden at least overnight). Also, if I decide to stop using a particular bullet, I can re-use that plug to match another bullet.

 

[StrutStopper]

I use Lee dies as well and I've never changed seating plugs. I have loaded RNFP in .40 S&W and .38 Special and haven't had any problems. Never did load anything other than RN in 9mm though.

 

[thefish]

I see now. Thanks skinned knuckles. That's an awesome idea. I'm going to try making my own plug.

 

[9mmepiphany]

You don't need a different die. Just a different seater plug (stem). FYI, RCBS die sets come with two stems. One for round, one for flat.

Yup

When I went to the Xtreme 124gr FN I just installed the flat nosed seating stem