510 Whisper

[Rob1928]

This is an update on my 510 Whisper project so far. It's a blast and I thought I'd share what I've figured out and also hopefully get advice from those who've already gone down this road.

The rifle is a Desert Tactical SRS Covert with a nightforce Atacr and Bowers Vers 50 can. The 20" 510 barrel is from Short Action Customs.

I used Quickload to narrow down suitable powders with the criteria of making 1050fps, 100% powder burn in the barrel, low muzzle pressure, and good case fill with the bullet .020" off the lands.

I finally settled on Blue Dot but my actual results were 150-210 fps slower than predicted. I finally realized that the long barrel was actually slowing the bullets down because the pressure drop off is so abrupt. Using the barrel friction feature of QL with a drag of 3125psi made my actual data match the predicted speeds within 5fps in all but one case and EXACTLY in a few others.

Max velocity occurs at 10-11", so down the road I may cut it to 16" or trim the foreend and SBR it. I filed a form 1 to build a can for it a few months ago so I may try porting it first and then cutting it down if it doesn't work out.

Here's what I've got so far from 85 shots:
750 grain AMAX, 3.600" OAL, CCI 200, Norma case

17.0 767fps
18.0 815fps
19.0 865fps
20.0 938fps
21.5 974fps
23.0 1037fps
23.4 1052fps
24.0 1081fps

My best group to date is 4 shots (first from a cold bore) into .69" with the last three going into .182" with 20.0 grains of blue dot. The longest distance I can shoot locally is 600 yards but this round only loses 200fps from the muzzle to 1000 yards which is hard to believe.

My next plan is to have a mold made to try powder coated pure lead bullets for possible hunting use and to reduce my Amax habit and also to come up with a load using Lehigh's huge hollowpoints.

Any other 510 shooters out there? Any advice or loads? Thanks in advance

[curtistactical]

That is just bad ass, I am baffled by the 200fps. velocity loss at a 1000yds. I think I need to look into this round. Thanks for the post.

[jwise]

I suppose the drop is considerable, as it is moving so slowly, but only losing 200fps at 1000yds is amazing!

[Wicked]

Nice stick. Congrats on a one-of-a-kind rifle.

You've already figured out a bunch on your own. I run 458 SOCOM bolt guns at subsonic-only which is a very similar type deal. Barrels over 12" or so are a waste. Bullets are expensive. Yes, have a mold cut. Worth the trouble to cast 'em yourself. I make my own for about 10% of the Lehigh match. Lyman #2 cast lead still doesn't expand much unless you hit something very hard. Controlled fracturing Lehighs with a payload bullet are the best way to go for hunting at range. For up close, a hard-cast wide meplat boolit will drill a big-ass hole.

I loose 205fps at 1000yds from the muzzle with the SOCOM - time of flight is 3.2 seconds. A 200yd zero needs -147 MOA to get to 1000 for my rig. A 20MOA base and NF NSX will get me -70MOA or 600yds. There, the bullet drops is 36 FEET and takes 1.8 seconds to arrive.



Next to the Lehigh 585gr match solids they are shorter OAL but more than 130gr heavier.



Dropped BB's and air soft pellets in the nose of the mold just to see what happened, it worked.



Powder coat is a pain. My first attempt to copper plate these:

[Rob1928]

Wicked, thanks for the info. Where did you get that awesome mold?

I've got a few hundred pounds of both Lyman#2 and pure lead as they are my two go to alloys in many calibers but I've only read about the pros and cons of powder coating vs other encapsulating lubes. I would greatly appreciate any insights you may offer. Did you find that plating was superior and powder coating not worth the hassle? They look great. Any tips are greatly appreciated.

My rig has 132 moa (+/-66) in the scope, a 40 moa base, and 20 moa in the retical which SHOULD get me out to +700 yards (+126 total) IF the bullet's BCs are correct at these velocities. With the 20" barrel and 10.5" net can I'm at 41" length, so I may be able to compact this without much performance loss if I go 16" or 12.5"

Along with cast bullets I'm going to play with spotter-tracer rounds as soon as snow cover reduces the fire risk. I can't wait!

PS: BBs in the nose of a soft lead bullet is a brilliant idea!!!

[strobro32]

Wow. I think I will tag this thread for retirement.

[Wicked]

Rob,

Cut the barrel. 16.5" would look great on that rifle. The extra tube is simply slowing you down, as you've already figured out. I'd love to experiment with a gain twist barrel as I think it could be the answer to stabilizing long heavy bullets at low speed in a very short tube. Never done it, but I want to try back-boring the rifling out to 12" in a 16" barrel just to see what happens. My Savage barrels are fairly inexpensive (compared to yours).

Still working on the plating thing but I think it's ultimately the way to go. Powder coat is proven but slow and messy, slow and messy, slow and messy. Plating is fast, like a bullet per minute with +.002" per side with my $15 set-up. I need to get pricing from a plater who could do a batch of 500 or so all at once. Wasn't difficult to do, but I'm not holding my mouth right or something and it isn't where I want it. The very narrow pressure grooves don't fill in and any gap in the plating could cause it to peel off. My home-built set up and lack of plating knowledge probably isn't helping me.

I'll PM you with contact info on the mold. Everyone told me you couldn't cast a long pointy bullet. Wrong. It was expensive though. But, you'll make it back in spades. I got a 66lb skid of Lyman #2 for $145. I should get about 650 almost 700gr bullets for around .22 cents each plus my time. Beats $2.35 a piece for the A-max's.

[Capt. Link.]

Rob,
I'd love to experiment with a gain twist barrel as I think it could be the answer to stabilizing long heavy bullets at low speed in a very short tube. Never done it, but I want to try back-boring the rifling out to 12" in a 16" barrel just to see what happens. My Savage barrels are fairly inexpensive

With the back boring are you suggesting a Paradox barrel.
http://en.wikipedia.org/wiki/Paradox_gun
A gain twist barrel can be cut with a sine type riffling machine.

[Rob1928]

Wicked, thanks for the info on the mold. I've used a few of theirs in odd calibers over the years and think they're top shelf. I recall seeing your mold in some other thread and wondering about where it came from then as you don't see too many or any, low drag cast designs. I'll check them out.

I'll definitely end up cutting it down. I almost went with 16" but wanted to play with max velocity supersonic loads and figured I could cut it shorter more easily than I could add to it! I'm having so much fun with the subsonics that I think that's all I'll do, so shorter it will get, I just have to decide if I should go to 16" or file the paperwork and go to 12" all at once. The form 1 I filled was for a 18.5" long can along the line of the Russian 12.7mm VSSK but I haven't worked out how I want to do the internals yet.

I definitely appreciate the economy of cast bullets and actually enjoy the casting a lot. I've shot a fair number of big animals with lyman #2 over the years and some of the bullets look like you could reload them. I've got a good supply of brass in this caliber and a big stash of lead so it will be almost like shooting for free compared to the $2+ Hornadys. In the mean time I've got a 308 barrel for this setup for a sanity check and to give my wallet a breather.

CPT, I think a paradox has rifling only at the muzzle, sort of the opposite of backboring from the muzzle. The idea was to have low friction for most of the bullet travel to spread out the recoil impulse and thus get away with a lighter gun but still have rifled accuracy. The secondary benefit was that there wasn't enough centrifugal force on the shot to make a giant donut shaped pattern with a hole for the bird in the middle. Never owned one but have had a few of the competing designs from the period. I think backboring might be a good way to avoid the SBR hassle and excessive barrel friction at the same time.

Thanks again for all of the input guys. I've learned a ton on this site and it constantly sparks 10x the ideas that I actually have the time and $$$ to pursue.

[este]

Wow. I think I will tag this thread for retirement.

Ha! Very apt. Cool build, but not a cheap or easy choice by any means. Looks good Rob, but a custom DTA barreled with custom ammo is FAR beyond anything I'd want to put time into. But then again, I hate reloading and hate tinkering. I want my stuff to just work.

Aside note: I can not imagine how pissed JD Jones must be every time he goes online, to a gun store, to the range and sees something about 300blk. I imagine him to be just so jealously grumpy about it. That "success" didn't happen for him.

[Wicked]

Aside note: I can not imagine how pissed JD Jones must be every time he goes online, to a gun store, to the range and sees something about 300blk. I imagine him to be just so jealously grumpy about it. That "success" didn't happen for him.

The business model JDJ applied to his pet projects was flawed. Marketing wasn't JD's bag and he wasn't big enough or cash flush. Robert and Rem/AAC crew understood 'the game' and they gamed it all the way to the bank. They admit they didn't create it, and only a handful know or care. That's business, not gun plumbing. There is a difference.

Slightly similar circumstances for Marty ter Weeme with the 458 Socom, but he appears to have gotten a wee bit more of the process right. Go to the 458 forum and listen to the girly bickering about who has the 'right' reamers. Stupid fools, it hurts everyone. A perfectly good cartridge will never be more than a passing fancy unless it's standardized. Publish the dimensions and everyone can feel confident they are getting good dope. Nobody likes secret s--t.

You simply can't protect everything from everyone. That lesson will be ignored time and time again, and those that do will suffer the same fate. Creative genius/engineering mastermind and financial success are not mutually exclusive, but are more often than not completely unrelated.

SAAMI approval is vital to the commercial success of most all cartridges. Otherwise they're doomed to a few wildcat die-hards and that's it. Licensing chamber dimensions is laughable. Trademarking a 'name only' product that can be easily duplicated is worthless. A million birds in the bush is worth more than 1 in the hand.

[Sealtee]

Wicked,

That is one good looking bullet! Would I be able to talk you into posting the name of the manufacturer of your mold? The closest thing that I have seen is from Lee, which I have. However it is not even in the same league as yours!

Also, I would be interested in finding out exactly what you are doing to plate these things. I understand that while your process might not yet be perfected, it would give folks like me a starting point to experiment with this process as well! Maybe start a new thread on this?

-Regards

[Sealtee]

Thanks for the info Wicked!

I will be looking them up!

[sjett]

I know this is a old post , but I'm building a 510 whisper and would like information on the bullet mold company WICKED used
Thanks

[hoser]

I am also in need of mold manufacturer info.

[jreinke]

Aside note: I can not imagine how pissed JD Jones must be every time he goes online, to a gun store, to the range and sees something about 300blk. I imagine him to be just so jealously grumpy about it. That "success" didn't happen for him.

The business model JDJ applied to his pet projects was flawed. Marketing wasn't JD's bag and he wasn't big enough or cash flush. Robert and Rem/AAC crew understood 'the game' and they gamed it all the way to the bank. They admit they didn't create it, and only a handful know or care. That's business, not gun plumbing. There is a difference.

Slightly similar circumstances for Marty ter Weeme with the 458 Socom, but he appears to have gotten a wee bit more of the process right. Go to the 458 forum and listen to the girly bickering about who has the 'right' reamers. Stupid fools, it hurts everyone. A perfectly good cartridge will never be more than a passing fancy unless it's standardized. Publish the dimensions and everyone can feel confident they are getting good dope. Nobody likes secret s--t.

You simply can't protect everything from everyone. That lesson will be ignored time and time again, and those that do will suffer the same fate. Creative genius/engineering mastermind and financial success are not mutually exclusive, but are more often than not completely unrelated.

SAAMI approval is vital to the commercial success of most all cartridges. Otherwise they're doomed to a few wildcat die-hards and that's it. Licensing chamber dimensions is laughable. Trademarking a 'name only' product that can be easily duplicated is worthless. A million birds in the bush is worth more than 1 in the hand.

Not only was his business model flawed, he didn't want to give the customer what he wanted. I contacted SSK twice in the early 1990's, talked to some flunky the first time and JDJ the second. I wanted an AR barrel cut to my specs and the response was basically "you buy it the way we make it or go somewhere else". At the time I had a TC Contender bbl in 300 Whisper, but TC screwed the pooch by only offering the barrel with a 1-10" twist. I should have just bought a SSK Contender barrel and have been satisfied. Instead I waited 10+ years and bought a 300 Fireball barrel from Model 1 Sales, F--k JDJ.

[Wicked]

http://www.neihandtools.com/