510 Whisper

Be careful -- low-volume ratio loads can detonate. Mangement not responsible for load data. Use at your own risk.

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ohnomrbillk
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510 Whisper

Post by ohnomrbillk » Thu Mar 24, 2016 8:15 am

I'm making my quest down the big whisper track. Looking for lots of info.

I have the SSK load data. Any other data would be most helpful.

I know guys are using WC680 as a great powder, but it seems like the sources for surplus have dried up. Anyone know of some for sale? Ranb's use of WC820 had me look for it as a second choice, but I haven't had any luck there finding it either.

I've read Ranb's posts on using his CBE 975gr cast Bullets. Anyone else having luck with a big cast pill? My suppressor is going to be user serviceable, so a big cast pill can be utilized without fear of lead buildup.

I'm having some brass made up, but would like to make my own. The reamer print I have shows a shoulder of nearly 90 degree angle. Are you guys cutting the shoulder that sharp? If so, I was going to use the Sinclair large caliber neck turner, but the cutters in them are 30 degree with a 40 degree available. Would I just have to grind my own cutter for the shoulder angle?

Do you think the little harbor freight chop saw many use to make 300 blackout should be able to rough cut the big case before final trim in the case trimmer?

quiettime
Silent But Deadly
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Re: 510 Whisper

Post by quiettime » Tue Mar 29, 2016 12:20 am

680 is the same as A1680 from what I've read

dirtjumper895
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Re: 510 Whisper

Post by dirtjumper895 » Sun Apr 17, 2016 11:10 am

I am also making the trek over to the big whisper. Where are you getting your brass made? I have used my harbor freight chop saw to cut the cases right behind the neck, but I have also used a copper tubing cutter with success as well. I then debur the case mouth, expand it to .508 to straighten the wall, and trim to length. I haven't gotten past this stage yet, I was looking into K&M's micro adjustable neck turner for the 50bmg, and have a call into them to see what their cutter angle is. I need 83° based on the chamber print.

Update: KM is grinding me a custom 83° carbide cutter. I should be starting to make brass by 4/25. I'll try and update with more info once it shows up.

I have not worked up any loads yet, but have some milsurp 690 grain FMJ and AP projectiles to try. I'm interested in casting the 975 grain pills, but that won't be probably til winter.

One thing I have noted is with Accurate detachable box magazines in 338LM, the 690 grain projectiles rub on the inside of the mag slightly which may cause the follower to slide upwards... still working on solutions.
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ohnomrbillk
Senior Silent Operator
Posts: 128
Joined: Tue Apr 14, 2009 10:08 pm
Location: NW Missouri

Re: 510 Whisper

Post by ohnomrbillk » Mon Apr 18, 2016 8:10 pm

dirtjumper895 wrote:I am also making the trek over to the big whisper. Where are you getting your brass made? I have used my harbor freight chop saw to cut the cases right behind the neck, but I have also used a copper tubing cutter with success as well. I then debur the case mouth, expand it to .508 to straighten the wall, and trim to length. I haven't gotten past this stage yet, I was looking into K&M's micro adjustable neck turner for the 50bmg, and have a call into them to see what their cutter angle is. I need 83° based on the chamber print.

Update: KM is grinding me a custom 83° carbide cutter. I should be starting to make brass by 4/25. I'll try and update with more info once it shows up.

I have not worked up any loads yet, but have some milsurp 690 grain FMJ and AP projectiles to try. I'm interested in casting the 975 grain pills, but that won't be probably til winter.

One thing I have noted is with Accurate detachable box magazines in 338LM, the 690 grain projectiles rub on the inside of the mag slightly which may cause the follower to slide upwards... still working on solutions.

I'm looking forward to your outcome with the K&M trimmer.

I have a guy that charges $2 per case to make them. Let me know if you want his contact info.

Is your accurate magazine CIP length?

dirtjumper895
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Posts: 13
Joined: Thu Feb 25, 2016 9:27 am

Re: 510 Whisper

Post by dirtjumper895 » Tue Apr 19, 2016 2:29 pm

ohnomrbillk wrote:
dirtjumper895 wrote:I am also making the trek over to the big whisper. Where are you getting your brass made? I have used my harbor freight chop saw to cut the cases right behind the neck, but I have also used a copper tubing cutter with success as well. I then debur the case mouth, expand it to .508 to straighten the wall, and trim to length. I haven't gotten past this stage yet, I was looking into K&M's micro adjustable neck turner for the 50bmg, and have a call into them to see what their cutter angle is. I need 83° based on the chamber print.

Update: KM is grinding me a custom 83° carbide cutter. I should be starting to make brass by 4/25. I'll try and update with more info once it shows up.

I have not worked up any loads yet, but have some milsurp 690 grain FMJ and AP projectiles to try. I'm interested in casting the 975 grain pills, but that won't be probably til winter.

One thing I have noted is with Accurate detachable box magazines in 338LM, the 690 grain projectiles rub on the inside of the mag slightly which may cause the follower to slide upwards... still working on solutions.

I'm looking forward to your outcome with the K&M trimmer.

I have a guy that charges $2 per case to make them. Let me know if you want his contact info.

Is your accurate magazine CIP length?

I may have the same guys contact info, shoot me a PM. My Accurate mag is 3.715". I am setting my action in a MDT chassis, and they use the 3.715" mags.
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dirtjumper895
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Posts: 13
Joined: Thu Feb 25, 2016 9:27 am

Re: 510 Whisper

Post by dirtjumper895 » Tue May 03, 2016 12:54 am

Finally got around to use the K&M Micro Neck Turning tool for 50BMG. After speaking more with Roger at K&M, the maximum cutter angle he could grind me is 77°. I got the K&M Expander as well to ensure the necks were expanded enough so the brass doesn't gall on the pilot. It took me a little bit to get the neck turner set up like I wanted, but it works great. The finished brass looks incredible, and the necks are very smooth and do not have any machining marks. I got the 50bmg setup with a steel pilot and carbide cutter with the custom grind. I also got a 0.005" depth micrometer which installs on the neck turner to get good measurements. I'm pretty happy with it so far, but it is time intensive. I'd say 10+ minutes per case. I did find out that it helps a lot to tighten the shell holder with a wrench, it eliminates any spinning of the case in the shell holder.

My process ended up like this:
1) Rough cut brass behind the neck. Debur and chamfer the case mouth.
2) Trim brass to 1.885". Debur and chamfer case mouth again. (I chose 1.885" due to it is 0.115" shorter than my chambers neck, and lets me crimp the neck later just inside the cannelure of my 690 grain milsurp projectiles)
3) Use 338 LM FL sizing die to full length size brass to minimum dimensions
4) Use K&M Expander die to expand case mouth to fit on pilot of neck turner
5) Lube case mouth and pilot on neck turner with good case wax.
6) Turn down neck to .0135" thick, in 3 passes. I set the shoulder at 1.440" from the base of the rim, as my go gage's dimension was 1.437" and the no go was 1.443" from the base of the rim. This should put me right in the middle of the headspace I was having my chamber cut to.
7) Use 510 Whisper dies to full length resize case ( Shouldn't be much happening here)

From here on it is normal loading. I'm waiting on my rifle to show up so I am only making a dummy round right now to ensure my settings are correct. But I dodnt know if my rifle or my can will show up first. My gunsmith was way backed up, and we all know how fast ATF is... The below pictures show the round by itself, and the round mocked up in a modified 300 Win Mag blind magazine I may try to use right now inplace of the Accurate Mag until I try polishing the inside of the Accurate mag for additional clearance.

Image
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ohnomrbillk
Senior Silent Operator
Posts: 128
Joined: Tue Apr 14, 2009 10:08 pm
Location: NW Missouri

Re: 510 Whisper

Post by ohnomrbillk » Mon May 09, 2016 10:36 pm

Your brass looks great!

What are you doing the initial rough cut with?

dirtjumper895
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Posts: 13
Joined: Thu Feb 25, 2016 9:27 am

Re: 510 Whisper

Post by dirtjumper895 » Mon May 09, 2016 10:52 pm

ohnomrbillk wrote:Your brass looks great!

What are you doing the initial rough cut with?
Thanks! I was pretty happy with how the necks turned down.

I've been recently using just a copper tubing cutter, but will be using my harbor freight chop saw once I can check my test piece of brass in my chamber to speed up production.

I bought a Chronograph over the weekend, so I am getting real close to be able to develop some loads once my barrel and action come back.
Play stupid games, win stupid prizes.

dirtjumper895
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Posts: 13
Joined: Thu Feb 25, 2016 9:27 am

Re: 510 Whisper

Post by dirtjumper895 » Fri Jun 03, 2016 7:28 pm

I got around to cutting brass using the harbor freight chop saw. It worked pretty well, but i did have to grind down the plastic housing slightly on the saw near the blade. Without this, the saw was only able to cut about 90% through the case.

Saw before grind down housing
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Saw after grinding down housing
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In process neck thickness check with KM Neck turner
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DOZER
New Member
Posts: 2
Joined: Tue Apr 25, 2017 2:01 pm

Re: 510 Whisper

Post by DOZER » Tue Apr 25, 2017 2:20 pm

New guy here, I'm in search of load data for this round. Along with a list of what I'll need to reload this. I have brass (I'll be making more). I just need to get the basics together

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