Idaho Sharpshooter,
That's two of us that are finally going to do it, eh?

Since AD 2000 people have been talking about it on these boards, various .510/.416 Rigby derivatives.

I am a recent convert to believing in small shoulders and I won't even badmouth the slight rebate of the RUM case anymore, seeing the success that The Weaponsmith has had with the AR line of cartridges feeding well in Ruger MkII M77's of standard length.

The .470 Mbogo shoulder is broad enough to stand necking up to grasp a .510 bullet. I believe!

Then a case full of H4831SC Extreme will give .500 NE ballistics with modern soft or solid 570 grainers, gentle and accurate, and in a faster twist barrel than the usual double rifle.

Or a case full of Varget Extreme with the same 570 grainers will WHOMP better than any .505 Gibbs, and no fillers needed.

1000 yard targets with 700 to 750 grainers anyone? H4350 Extreme and a full case.

The .500 Mbogo will do it all, and then some.

i might be #6 or #7 depends on, well you know...if i have a good year maybe #3 i have a few more rifles in line first. keep us soontobe's (no jokes please... )updated

quote:

1000 yard targets with 700 to 750 grainers anyone? H4350 Extreme and a full case

so how would it work...i assume you would long throat for bmg bullets but how would it do with reg 500ne bullets???

BS,
Only 0.3000" of parallel sided freebore length is needed to seat and crimp the blacktip AP bullet on its usual cannelure.

The .500 A2 comes with 0.4000" as its standard.

0.5000" of freebore will be enough to handle the 750 grain Hornady A-Max seated way out there, as far as I would care to go with my latest understanding.

This is less freebore length than the caliber of the bullet. I do not think this will be detrimental to accuracy with 570 grainers and it will keep pressures down.

Give it a 1.5 degree leade to finish the throat out.

sounds great!

Botswana Kopje Top To You Too:


where are the list of the ha doa carts?
sorry had to find a use for this one...

so is it safe to say the 500 mbogo will be the best d.g. cart bolt rifle combo?

quote:

Originally posted by boom stick:
so is it safe to say the 500 mbogo will be the best d.g. cart bolt rifle combo?

Only for those able to handle it to its fullest potential ... take your .375 H&H or .375 Weatherby as backup.

2400 fps with 500ish grainer flat point solids would be my reg load...low preasure. use 750 gr a-max for plainsgame

i think dave the mbogo creator should have the first one...or at least shoot it first.

quote:

Originally posted by boom stick:
use 750 gr a-max for plainsgame

That would be one heckuva big Ballistic Tip for impala and warthogs.

BTW, HA!/DOA will never go public. In fact, it has now gone very private. It has always been Joke Schtick, appreciated by a few only.

what happened to share the wealth ect ect ect???

you are changing your business structure as much as i am getting fired



sorry...

20 for $26 at midway...not bad

that would make a nice suppository for a kudu

Good picture to show how little freebore is needed to seat that needle nose out to 4.750" COAL.


The bullet length is about 2.560".
The boat tail is about 1/3" long.
The .510 caliber shank of the bullet is about 2/3" long.

More than 1.5" of bullet nose projection is possible with ZERO FREEBORE, just using the leade.

Ballistic Coefficient = 1.050
Supersonic and accurate past 1000 yards from a relatively "featherweight" rifle. Kudu beware!

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=741395


Barnes Original Bullets 50-110 WCF (510 Diameter) 300 Grain Flat Nose


would these function for plinkink and jackrabits to deer? i think they would just explode in a good way

Now we have exceeded the bounds of etiquette for sure!

Lessee, .470 Mbogo ...

Wow, you guys are like a kids in a candy store! Little do you know, the candy is spiked with hot pepper! hint of sweetness at the start, then knock you on yer ass heat! Kinda like the recoil of the 500, huh?!

Anyhow, if one were to order said barrel from Pac Nor for the 470, what muzzle OD would you get for a 24' tube?

Ron,

The 1-7 did increase velocity a bit, from 3250 fps to 3300 fps with M193 ball but this was august in Quantico, Virginia (1982) and alot of that could have been temperature and humidity.

SS109 (later type classified as M855) was 3150 fps in a 20 inch tube and about 3050 fps in the 18 inch M249 prototype (Minimi).

Quick twist was only necessary for the M856 tracer which was long as a bad dream. 1-9 was adequate for 62 grain M855.

New ammo used slower powder (slightly), so all of pressure curve may not have been due to 1-7 twist.

Production A2/A3/A4's use a smaller diameter gas port than A1, so that does prove the pressure curve moves down barrel.

For DGR I dont think it matters.

If you are shooting a 115 gr. 6mm X or 140 gr. 6.5 x 284, or 175 gr. 7.62 Nato at 1,000 yards, a 26-28 inch barrel and 1-8 or 1-7 twist might matter but for what we all do here it does not, unless you want a little extra penetration for FMJ.

My tests certainely demonstrate it does make 10-20% diff w FMJ, though it is probaly impossible to stabilize a monometal SD 330 at any twist or velocity.

PS do not put TBSH solid in same category as a conventional FMJ as the light weight front end and lead base make it very unstable. It would make a great anti personell weapon. For a FMJ you want a cylinder, with its CG equal to its center of form. Ask any PH who has ten years experience and they will tell you the TBSH solid bends and veers off course. It is hard up front w solid brass, aand that makes sense, but that moves CG to rear so it upsets. Sounds esoteric I know but thats what happens!

AT

Andy,
Thanks. Good info.

gixxer,
Most seem to like the .470 Mbogo barrels to be 0.750" diameter at the 24" muzzle or thereabouts.

quote:

Originally posted by 500grains:
I have not experimented with twist rate versus penetration as Ron has. .

Wow, things were a little clearer 6 months ago..

Ron Iron buffalo results, shooting his iron buffalo, are posted here
https://forums.accuratereloading.com/eve/forums/a/tpc/f/...=835101865#835101865


wasn't it nicer when folks said "i don't know".. or "i don't know, but I would like to try"

?

quote:

Originally posted by jeffeosso:

wasn't it nicer when folks said "i don't know".. or "i don't know, but I would like to try"

It would also be nice if we had forumites who had an attention span of more than 5 or 6 words...

RIP- Just how many times have you shot your .470 MBOGO at 500 or 1000yrds? Have you ever shot anything at those ranges? Don't think I've ever seen you at any US 1000yrd benchrest matches but maybe I'm wrong. Been to a few though! Got any groups to post? Gee, Overtwist won't hurt at these ranges. Wanna Bet? Now there is a new concept that just about everyone in competative shooting probably rejected 100 yrs ago. Time to stop propagating this BS. -Rob

Rob,
Rip has seen the light and published his results, that a head to head comparison of fast and standard twist makes no difference in penetration in his iron buffalo.

jeffe

quote:

Originally posted by Robgunbuilder:
RIP- Just how many times have you shot your .470 MBOGO at 500 or 1000yrds? Have you ever shot anything at those ranges? Don't think I've ever seen you at any US 1000yrd benchrest matches but maybe I'm wrong. Been to a few though! Got any groups to post? Gee, Overtwist won't hurt at these ranges. Wanna Bet? Now there is a new concept that just about everyone in competative shooting probably rejected 100 yrs ago. Time to stop propagating this BS. -Rob

Rob,
You are just being a knobhead here.
My .470 Mbogo has a 1:16" twist.

Get un-confused.

The differences with twists from 10" to 18" are trivial in a .475 caliber hunting rifle.

The differences with twists from 10" to 15" are trivial in a .510 caliber hunting rifle.

The faster twists do make the rifles more versatile hunting rifles with the longer monometals as well as the shorter lead-cored bullets of yore, all work well at hunting ranges on big game.

You may obsess all you want about 1000-yard matches between your 15" twist 50 BMG and my 16" twist .470 Mbogo, but I assure you it will never happen.

Get over it.

sounds like RIP needs one of those RSVP invitations to the twist party.

Rich

Rich,
Let me know when the party includes ordnance gelatin.