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I have a custom 7-08 that will not shoot worth beans with 140's in a lead/copper version but will make bug holes with TSX's. Several have worked with the gun and lead/copper bullets with all being able to get approx. 1.25" groups. With the TSX's .6-.4 groups are norms even with factory Fed. premium 140's tsx's. Now for the questions---1st. is the twist rate possible slow for the lead/copper 140's.. 2nd question-- although it has not been tried is it possible that heavier thereby longer lead/copper bullets would give a much better group than the 140's lead/copper. All suggestion welcome. Thanks

In BR shooting I have found that some barrels like some bullets and not others. This is with the same twist and same weight bullets. Some bullets are shorter, fatter, and have more bearing surface. Some are longer with a higher ogive number. It would be nice if you could have one bullet that would do it all.
Butch

Answer to 1: No. If the twist rate were to slow the TSXs would likely not likely shoot well

Answer to 2: Yes, but likely because it just a different bullet.

Try varying the seating depth on your C & C 140s. This could well be a throat length issue.

I've had barrels that seem to be OK (looking through Hawkeye bore scope) but I was never able to get them to shoot.

Barrels seem to have rules of their own.

Thanks for the information, Guys.

140s are pretty easy to stabilize- I don't think it is a twist issue. More than likely, it is a size issue. Try a 168 Sierra Match king and see if it will shoot better, they have been the easiest bullet to shoot out of any 7mm I have owned- the 154 Hornady a close 2nd.

dennisinaz, what do you mean "size issue"? Do you mean weight of bullet or what? I like shooting 140-150's even in my 06 cause the deer here aren't very large and even a big hog will drop like a ton of bricks with a 223 put in the right location.

The .284 Barnes TSX bullet is 1.34 inch long. A Sierra 140gr SPBT is 1.16 inch. As expected, the Barnes all copper bullet will be longer than a similar shaped lead core bullet since copper is less dense than lead. Since the minimum rate of twisted needed to stabilize a bullet is predicated on the length of the bullet and not the weight, you need a faster twist to stabilize a longer bullet of the same caliber. So if your barrel stabilizes the Barnes, it will stabilize a 140gr lead-core bullet just fine. So answer to question #1 is a resounding NO.

Question #2 is a definite maybe or rather yes, it is entirely possible that your barrel/chamber likes longer bullets like the 140TSX and you should definitely try longer (heavier) lead core bullets. I also agree with MILES58 that you should try varying the seating depth of your lead-core bullets.

Guys, I want to thank you again for the tips. The 7-08 is now making bug holes with 140 TSX's .2" in group size. The very first loading, groups shrank to .6-.4 and then by moving the bullet .040 groups shrank to .2", so small that my buddy doing the reloading had to take several looks at the groups to be sure that 3 shots had hit. I am tickled to death with the gun now and cannot wait to get it in my hand, buddy lives 250 miles away. BTW this is a lightweight rifle (7.25lbs with sling & loaded). Buddy said we would work on some C&C bullets later and see what happens.

Did you move the bullet towards the lands (seated out), or further away from the lands (seated deeper)? Barnes bullets like to kiss or be VERY close to the lands for best performance. Nicely done. Post pics of the rifle and the groups Flinch

Flinch...I have found in a select few rifles, they shoot Barnes best when seated way off the lands...others, indeed most others, not so much...
But I always try them both ways...sometimes the "jump" they like is almost alarming...

I have found that Barnes bullets are extremely picky about seating depth and it usually takes me a $100 in bullets to figure out what a rifle likes. Once I find the sweet spot, it is pretty darn narrow for a given rifle. I don't shoot a lot of them for this reason. I use them in .223's, 22-250's and hot .25's when shooting big game, but that is about it. Basically any caliber that shoots them over 3,300 fps. They work well at high velocity. The other calibers allow for more shooting with less expense bullets and still kill well Flinch

+1 on everything you said...load development is usually expensive, and yeah, I like them in the small bores best...

You and Flinch are weird. I like them best in 270s and 30 cals. Fast is better though. I don't like starting them under 3000. I have done only a couple .223s, 5 .243s. half a dozen .308 Wins, 4 .270s and 15-20 30-06s with the odd 300 WM and 25-06 thrown in.

I won't accept less than an inch, and I start at .050 off normally. If that doesn't shoot I move up to .010 and start backing up .010 at a time. A surprising number of rifles shoot well, some really well at .010 off. Like Ingwe, I sometimes find the sweet spot so far back it's worrisome. Usually when I find one that needs to be so far off, it also tends to be extremely picky about the depth. .010 to little or too much and I have seen them throw 8 inch or bigger groups, something I do not see with the ones that need to be close to the lands.

The ones that are picky about just the right depth worry me a lot that working up the loads when it's warm and shooting Bambi when it's cold. I haven't tested it, but I am betting it won't shoot like it did during the work up when it's down to zero.

Interesting that I've found that Barnes can do well from close to, to very far off lands.

I've also found that with the exception of 2 rifles many years ago prior to TSX, its rarely taken more than half a box of Barnes to know that I"m close and I can tweak a bit from there on. Of course I start shooting/hunting them right away once I"m zero'd and around an inch or hair under.

Both of the above rifles were proven shooters... well under MOA with C/C bullets but would not shoot with Barnes X bullets.

Miles: I have used the TSXs in both my 7x57 and Ingwewifes .30-06..both to VERY GOOD effect...
I just havent shot anything bigger than deer in 5 years, so the little guns get the nod...my 7x57 is now my "big" gun, and it gets stoked with 160 TSX..


You just figgered out me and Flinch were weird...?

If your rifle is really shooting that good you would be a fool to do ANY more load development. That is a one in a million rifle and you have found the perfect combination. Buy 20 more boxes of those bullets of the same lot number and use this rifle for some long range hunting. Forget cup/core bullets. Why bother...

I have a 25-06 Sendero that has several boxes of 100 grain TSXs down the barrel and still shoots at best 1-1/2 inch groups, with most being 2-3 inches. Run 75 gr VMaxs through it and all the holes touch with about any charge of Varget I've run through it.

I solved a 30-06 Parker-Hale that shot extremely well with Sierra 150 FBs (the only hand load I tried in it) by UBCing the bore. That one fouled badly enough that anything after the third shot with a Barnes just opened out past 3 inches. After the UBC it would shoot at least 8-10 without losing accuracy.

The 25-06 sits in the safe with a 4.5-14 conquest on it. I bought it to reach a ways with the TSX 100s. I haven't been able to even find any TTSX 100s to try yet

It CAN take longer to solve some problems when your perspective is abnormal to begin with you know.

DLALLDER,

Listen to Dennis! If you do not run out and get as many of that lot of bullets as you can right now, I can guarantee you will be regretting not doing it. I wouldn't hesitate to put a couple pounds of that powder lot aside too. While you are still friends with the loader, get him to load up at least five boxes for you. You never know, he might just step out the door and get smacked by a bus.