I have a pre 64 feather weight ,in .308. I have never been able to get it to shoot quite as good as I had hoped for when i bought it.
Since the rifle is no colectors item, i was thinking of making a custom out of it or trading it for a nice savage 99. But 1st I decided to go away from my favorite .308 powders, (RL-15 & Varget). Got some IMR 4064 and things got better quick. then I tried the 168 grain tripple shock Barnes. 1st 3 shot graoup .85. Then 5 shots put her dead on at 200. I had similer results with my fussy ruger ultr light in .257 R with the 100 grain tripple shock. I hope I can find a cheaper bullet for coyotes, gonna try some this weekend. But I don't mind spending a little xtra money for my big game bullets...tj3006

Hey TJ:
I just loaded some 30.06 in the TSX & wow! even out of a new un-broken-in barrel it was right at 1" after my first try. I'm going to try the TUBBS Final Finish system & then work up a little bit different load to see if it will tighten up. Good luck
TAz

TJ: what made you decide to try the TSX?

TAZ: What is the Tubbs finishing system?

Doc:
It's an interior barrel finishing system.You use it by shooting bullets that have an abrasive coating on them which in turn polish the barrel. I've never tried it but a buddy of mine says it increases accuracy & reduces fouling, so I'll give it a try & see. I'll post the results as soon as I load up the rounds. http://www.davidtubb.com/finalfinish.html

I just like to try lots of bullets, And i learned with my little ruger .257 roberts that the tripple shock is a really different animal. Meaning it performs differently than a more conventional bullet. I would love to try them in my .338 but they are very expensive.That tubbs system is not a bad idea but if you are getting a 1 inch group I would not use it. It certainly excelerates ware on your barrel, that after all is what it is designed to do ! My 270 seems to be rather rough and i may ty it in it But if your rifle is shooting MOA , I don't think it needs any fixing ! ...tj3006

Doc, I've tried the Final Finish system on a Rem 700. Didn't accomplish anything that I could tell.

quote:

Originally posted by DeltaHunter:
Doc, I've tried the Final Finish system on a Rem 700. Didn't accomplish anything that I could tell.

Check your throat before and after. I've seen internet posts (take that for what it's worth) where people have said that it has washed out their throats significantly after use.

Does Tubbs mean his process to work on polishing cut-rifled barrels like the pre-64 barrels which are already pretty smooth, or does he mean it to lap button-rifled barrels?

Jaywalker

TAzfla,

You might want to reconsider the tubbs polishing and do what barnes recommends on their site. There have been some documented cases where the throats have been widened considerably. As FJold has said, I just hate to see you do this and then have to rebarrel. The problem is that the abrasive is all worn off in the first few inches and that doesn't smooth the entire length of the barrel. Barnes recommends you use a hard bullet made of gilding metal(copper, brass and zinc combination like Hornady or Sierra or Speer) to break in a new barrel. The procedure, am paraphrasing goes that you should clean the barrel with copper solvent so that it is bare steel to bullet. Shoot once, clean. repeat that 10 times. Shoot twice, clean, repeat 5 times. Shoot 5 times, clean. repeat 5 times. Then shoot the barnes again after cleaning thoroughly. You should smooth up fairly well after between 50 and 100 hard shelled bullets. Don't risk the new gun on the tubbs dude!!! I have a new custom .375 that am breaking in so know where you are there...my $0.02 worth.

On the original post, Thomas you will find that a well taken care of rifle that has a smooth bore will shoot the barnes driving tacks. My model 9705 will shoot ..19 group at 100 and will usually place in the long distance shoots around here...800, 900, 1000 yards. The barnes really has no equal as far as balance. They are expensive however, you can find them many times on ebay for a much reduced price. I recently bought 5 boxes of .375 for $10.00 a box plus shipping. Many folks are going to the triple shock and, if you don't mind the older technology, which is just fine btw, the xbt is almost always on sale there in the .308 caliber. Mine really likes the 180 xbt and the 168 tsx bt...enjoy!!!

TJ, have you ever checked what your .308's twist rate is?

I found with my 1969 Brno .308 that I get the best results with 150gr and lighter bullets. Worst groups with 180gr bullets.

Reason: 180grainers are longer than 150grainers and because my .308 has a 1:10" twist and not the standard 1:12" twist, the longer bullets tend to give poor groupings and can result in you missing shots at game.

Worth checking it.

I have used the standard barnes X bullets too. The 150 grain XBT was very good in my 7mm STW. half an inch and I think 3400FPS. I want to try the 160 grain tsx in the same rifle. I have been playing with mostly my der rifles latly and i have prety much picked my rifles and loads. With the .308 shooting the 168 grain tshock so well and the little Roberts doing the same. I think the roberts will be the rifle I hunt with and the .308 will be my back up.
It should point out that my 30,06 shoots the same tripple shock 168 grain very well too and I fired 1 over the chroney and got just over 3000, fps. I would use that one but i get well over 2800 with the .308 and it is a little easier to carry around.
In my roberts the tripple shock has shot right arouynd MOA and given me 3100 fps, with the max load right of the barnes manual.
I have confidence in that load out to 400 yards witch is probably farther than I should shoot unless I get the perfect setup.
can't wait to try the 100 and 115 grain tripple shocks in my 26 inch 25,06 witch should be finised soon !!! ...tj3006

osokosniper,
really appreciate the info. I've been away from the site & just read your post with the suggested way to smooth out the barrel. I called them up prior to using the system & explained the gun specs & they said to only use #3- #5 in the box of 5 different bullets. A total of 30 shots cleaning well after each set of 10. Up to now, using the Barnes 168gr TSX, 58gr IMR4350, the Tikka T3 is shooting better than I'll ever be able to & the throat & barrel look mint. Maybe I just got lucky. But thanks again for the help. Sootem straight

This sounds to me like a better idea.


Fire lapping very basically involves shooting a soft, BHN 11, oversize bullet impregnated with a high grade lapping compound through the bore of your firearm at airgun velocities. These abrasive bullets act like self conforming lapping plugs which incrementally remove constrictions in the barrel, uniform it dimensionally and smooth out the tooling and chatter marks in the rifling. Complete fire lapping step by step instructions may be found in the fire lapping chapter in the Beartooth Bullets Technical Guide.
In virtually all firearms it will either greatly reduce or totally eliminate both barrel leading and jacket fouling by smoothing out the tooling marks left in the barrel by the equipment used in barrel manufacture and by easing the sharp corners and edges inside the bore which collect fouling.
In most guns, there will be at least a modest increase in accuracy potential, to often times dramatic improvement in accuracy from increasing the uniformity of the bore dimensionally, and eliminating the constrictions which are common under dovetails in barrels, and barrel bands.
Especially in revolvers where the threaded barrel shank is screwed into the frame of the revolver, dramatic improvements in performance may be achieved. This is particularly true where cast bullets are used in the revolver, because the constriction under the threaded barrel shank (which can be from .002"-. 004" depending on make and caliber), acts like an undersize, bullet sizing die, thus sizing the bullet down under barrel groove dimension, creating an improper bullet to barrel fit. Not only does this condition deteriorate accuracy; it also promotes barrel leading. Fire lapping, properly done eliminates this conditionan.
Finally, fire lapping often times increases the nominal velocity achieved with a given load. This is accomplished by a reduction in the friction coefficient of the barrel. Lapping out even a small portion of the tooling marks in a barrel will reduce the friction coefficient of the barrel, at least to some extent.

A Note Of CautionYou will notice that the first paragraph about fire lapping specified the use of soft BHN 11 oversize bullets. There is a reason for this. The soft bullet will conform and swage down to the tightest part of the barrel, and not "spring back" to near original diameter due to its softness. Thereby the most aggressive cutting action in the barrel is at the point of constriction, and the remainder of the barrel basically gets no lapping action once that soft lapping bullet goes through the constriction. A harder bullet will "spring back" to some degree, and basically lap all parts of the bore at the same rate, thus enlarging everything uniformly, and not addressing the tight spots specifically.
I also mentioned oversize bullets. This is to insure equal lapping action not only on the tops of the lands, but in the bottoms of the grooves at the point of maximum barrel diameter as well. If the bullet is less than maximum groove diameter, it will only wipe off the tops of your lands, thus reducing the actual depth of your rifling. There is a popular practice out there in the shooting industry today to use jacketed bullets for lapping. Please use caution, and consider what I just presented, and the following concepts. Most barrels today are .0005-.0015" over what nominal accepted norms are for bore dimensions. Consequently, when lapping with jacketed bullets the only part of the barrel that gets lapping action is the tops of the lands and the bottoms of the grooves never get touched, which is where most fouling and leading occur, not to mention reducing the depth of your rifling by only wiping out the tops of the lands. Fire lapping isn't complicated, but it is tedious, and must be approached systematically with common sense.

Jagter I couldn't help but notice that you said your rifle is a 1:10 vs 1:12. If anything, the faster twist should help you with those longer bullets?

I guess I need to get up the nerve and run some of the TSX's through my 700 Classic in 300 H&H. I've run everything under the sun through that thing and can't get it to reliably shoot anything. At first I thought it was because the stock was touching, but that problem has been resolved and it still shoots like dung. Go figure. I'm headed down to Cabela's next week probably to buy a gun anyway, so I guess I'll grab some of the 168 gr. TSX's while I'm there.

quote:

TJ, have you ever checked what your .308's twist rate is?

I found with my 1969 Brno .308 that I get the best results with 150gr and lighter bullets. Worst groups with 180gr bullets.

Reason: 180grainers are longer than 150grainers and because my .308 has a 1:10" twist and not the standard 1:12" twist, the longer bullets tend to give poor groupings and can result in you missing shots at game.

Worth checking it.

Did you not inadvertently swapped the figures around?

A 1-in-12" barrel is supposed to be the slower one, and hence it is the one that would have difficulty to stabilize the longer and heavier bullet (180 grainer).

Chris Bekker

KF & t:

On a .308 with a twist of 1:10", a fully stabilized bullet with a weight of 130gr (150gr and less) fired at a MV of 3200fps, as Jagter is doing - refer his other posts - is just almost perfect.
Up to a 160gr would be OK for this rifle on high velocity.

Over that weight with high velocity rather go for a 1:12" twist.

BULLET STABILITY CALCULATIONS

SF stability factor (no. units);
V bullet velocity (feet per second);
BL overall length of bullet (inches);
WT weight of bullet (grains);
TWIST rate of twist (inches per turn);
DIA bullet diameter (inches).

Stability Factor Calculation
V 3200
BL 1.15
WT 130
TWIST 10
DIA 0.308 SF = 3.35


Maximum Bullet Length Calculation
SF 3.35
V 3200
WT 130
TWIST 10
DIA 0.308 LENGTH = 1.15

Minimum Velocity Calculation
SF 3.35
BL 1.15
WT 130
TWIST 10
DIA 0.308 MV = 3198

Minimum Twist Rate Calculation **
SF 3.35
V 3200
BL 1.15
WT 130
DIA 0.308 TWIST = 10.0

** NOTE : The LOWER the number, the HIGHER the rate of twist (spin)


The 130gr GS Custom HV with a bullet length of 1.15 inches fits all the above requirements like a glove!