30 Gibbs vs 30-06 , in a 28" tube

[Guest]

I've got a 28" Mike Rock barrel on the way that is currently chambered for the good old 30-06 , my question is how much velocity would be gained by go to the slightly larger 30 Gibbs.

The gun will be used for deer and hogs out to 600yds , bullet will brobably be either the 180gr Accu-Bond or the 175gr MatchKing
Brass will be Lapua.

 

[REM 700]

I had my 30-06 rechambered to 30 gibbs and gained 150fps with 165 gr. bullets

 

[308sako]

While this doesn't quite answer the question, My .30-06 AI will do approximately 100 ft/sec faster than a regular '06. It really isn't worth the trouble, and the best way to prove this to yourself is to run some realistic ballistic tables to the above mentioned yardages. If you want considerably more speed use a bigger cartridge, the 28" tube should be able to help out some of the slower powders when paired with a heavier projectile. I'd imagine that with enough R22 or similiar with the 175 or 180's that close on 2900 ft/sec's should be yours for the taking. Years back I chronographed some factory 180 grain .300 Winchester ammo which was in the low 2900 ftsec range. This was from 24" barrels. AI's and Gibbs while interesting and good conversation pieces are much trouble for little real gain, IMHO

 

[sniper2]

I have a friend who shoots the 30 Gibbs and uses WMR and gets vel near 300 win mag.
It is just a matter of personal preference
how much is enough or what do you want to go through to get to a certain end.I like the wildcat cartridges Gibbs,Ackley and the others but some may not, to each his own!

 

[Guest]

Well I was thinking that with the extra few inches of barrel and the tight bore that I maye be able to get into the 300Win velocities pretty easy , I've got a 30-06Ai with a 26" Lilja tube that will run the 180gr Partitions out at just over 3000fps easly.

I guess I'll see what it will do as a standard 30-06 first

Hell who knows maybe i'll give the 300 Dakota another try.

 

[Mysticplayer]

I have run a 30Gibbs and it is one of my favorite wildcats. There is an increase in performance and that is sig when ranges get out there.

I have a slow '06 at 2750fps for 165gr bullets. My Gibbs took the same bullet to 2950fps accurately. Could go faster but then I had a shotgun. My guess is that your 28" tube would be around 3050fps with the 165gr bullet, and close to 2950fps with the 180gr. Very close to the 30 WSM and 300WM.

With the lower BC of these bullets, I liked the idea of reducing wind drift and increasing impact vel/energy. Small but a definite difference. You gain another 100yd in performance.

Same reason why people use the 300WM. There really is only a small increase in vel over the '06 but that has not detered the thousands who use it.

I have sold my gibbs and replaced it with a 6.5-06. The reason, wind drift at ranges beyond 500yds. As good as the 165gr SST is, the 140gr SST is head and shoulders above it.

At basically the same muzzle vel, the 6.5 is hitting harder at all ranges because of higher retained vel. The reduced wind drift is amazing.

Comparing the gibbs and '06, I would go Gibbs. Between the 30Gibbs and the 6.5-06, 6.5 all the way. I would have built a 6.5Gibbs but my action will not feed the sharp shoulders.

A 7mm Gibbs/280AI/7JRS would also be on my possibles list. Something to think about if you haven't bought the barrel yet...

Jerry

 

[Guest]

Well I already have the barrel or at least have paid for it. I guess that I'll shoot it as a standard 30-06 and see what it will do.
The ranges it will be used are well under the 100oyd mark probably 700 at the most , generaly between 400 and 600 yds.

Jerry , would you happen to know what the BC of the 165gr and 180gr SST bullets are ? How do they stack up akainst the A-max ?

 

[Kevin]

The gibbs provides a pretty significant change. I have a 30 gibbs with a 30 inch tube, I shoot the 190SMK and 190 JLK at just over 3000fps

 

[Mysticplayer]

JDJones, I have not used the 180gr SST so can't comment.

I compared the 168 gr Amax to the Nosler 168gr J4 (very similar to the MK) and 155gr Amax in my 300Wby. At 650yds, the 155gr Amax arrived with less drop then the 168gr amax, which arrived with less drop then the J4. Both 168gr bullets left with the same vel and the 155gr left 125fps faster.

The trajectory I am getting in my '06 and 165gr SST is pretty flat. Putting the numbers in a ballistics program gives me more goofy results (see my thoughts on the 6.5 140gr SST).

My muzzle vel is 2700fps with the 165gr SST. I use 28 min to go from 100 to 1000yds. Let's just say that it is higher then 0.5. The SST is longer then the Amax.

The 165gr Interbond is longer then the SST so should be even higher in BC. I am not even going to go there.

I have not come across any bullet in this cal weight class that flies as flat as the Hornady bullets.

Jerry

 

[Carbonman]

Interesting thread....
I have burned a lot of powder through long barrels in the /06 and wildcats based on the /06.
For long range hunting purposes I have switched to the Lost River J36 165 gr. bullets. Nothing else compares in performance on game and competes with a B.C. of .636.
Accuracy is better than a couple years ago too. The quality control procedures at LRB have improved greatly over the last 16 months.
For the 30/06 I run the J36 on top of 56 grains of VV N550 in a Lapua case torched by a CCI LR BR primer. This gives an average of 2996 fps out of a Rock 5R 28" tube. Pressures per the strain gages average 58336 psi. Groups are in the high .3's and low .4's.
I have over 1000 ft.lbs. of energy left at 800 yards and a wind drift of .5 moa/10mph at that distance.

For the 30 Gibbs using the same components and increasing the charge weight to 58.5 grains yields 3054 fps. Pressures run 58395, accuracy is similar.

For my money, the hassle of fireforming the Gibbs doesn't pay off in performance downrange. Don't get me wrong, I like the Gibbs series, however, the only Gibbs I currently use is the 240.

There's a lot of wildcat data out there and a lot of stories about radically increased performance. Many of the wildcat loads I see are running pressures that I don't want next to me at the bench and certainly don't want close to my face.

Bottom line is the /06 works fine for me out to a little past 800 yards. If I need more reach, it's time to reach for more horsepower. My definition of more horsepower is a big 338 based on the 505 Gibbs case with 300 gr MK's at over 3000 fps.

Just my unsolicited $.02.
(All loads are maximum loads and safe in my firearms. Readers must reduce 10% and work up from there, yada yada yada, legalese bs etc.)

Mike

[ 10-01-2004: Message edited by: Carbonman ]

 

[Guest]

Well , I got to shoot the barrel yesterday
I had loaded up a few loads and seated them to book specs.
Here Are the top velocities that I can up with

155gr A-Max , 62gr of H-4350 = 3247fps average
168gr A-max , 61gr of R-22 = 3018fps
average
178gr A-max , 59gr of R-22 = 2937fps
average

Accuracy was well under the 1moa mark , I pretty sure that with a little load developement I can improve on the velocities and alot on the accuracy.

Mike , do you like that VV550 pretty well ? how is it as far as consistancy and temp tollerance ??
Hey bud thanks again for the barrel

 

[Carbonman]

JD,
I like the VV high energy series of powder. It isn't quite as stable as Varget, however, it beats a lot of others in thermal stability. Lot to lot variation has not been an issue for me. It kinda hurts still when I pay for VV powder or LRBT bullets, but I think it is worth it.
I'm the kind of guy that has been a real cheapskate at times when it comes to components. Know anyone else that builds a complete rifle because you have 8 lbs of a certain powder, 300 bullets and a die set?
Bought a reamer and dies off of ebay for the 220 Ackley Swift. (saved a bunch of money) Hmm, barrel, action, stock, mounts, rings, optics all kinda added up. But did I mention I saved a bundle on the reamer and dies!

Mike