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Mag Length Copper Bullets and Bullet Seated Deep Into Case

Has anyone noticed accuracy diminishing when loading bullet further into the case to make magazine length? Pressure would probably change bullet speed and compressing powder would probably change flight. Any ideas? Thanks for looking
 
I would need to think about it on a case by case situation. Since I do not know your situation I will give you the cover my butt answer first. I would back down the charge and try it. I have personally done it on a few rifles and have not blown up any rifles. In one case it was a belted magnum and it did not seem to damage the powder. Accuracy did not change. I did this to a 308win and accuracy went south. I was really compressing the powder and I think I damaged enough to affect burn rate. I did not crimp and there was plenty of jump. I backed down the charge to what basically filled the cassings with the bullet and accuracy did come back but not as much. It was still good enough for hunting so it worked.
 
-Turn necks to remove donuts.
-Partial length neck size.
-Test for best seating even with length limitation.
-Powder develop load with best seating.
-Manage your sizing to mitigate future donut formation.
 
My 308 with AIC mag will not shoot TMK 168 without pressure, at mag length. Let it hang out as designed and it shoots well.
 
Not sure if you mean .308 or .223. I've had more success maintaining accuracy and decent velocities with mag length copper bullets in .223 than in .308. Go with a 50 grain TSX or TTSX.

In .308, I've had a lot of challenges with 150-168 grain copper bullets (various types and brands). I gave up, but my next try would be a 130 grain TSX or TTSX.
 
Both the rifles are Sakos in 300 WSM, they have different barrels. Just trying not to shoot them out with excessive load testing. The Barnes tipped are so long I will look at the Nosler and Tac bullets. Thanks for the replies.
 
Here's the thing: Both rifles are Sako 75 Stainless/Synthetic with their removable magazine. With these magazines the COAL is limited to about SAAMI max length and the non-toxic bullets required to hunt in California are very long. Has anybody found a solution that will work in 300 WSM cases at SAAMI max with non-toxics in the 165 to 180 grain range - accuracy over speed, safety over both? Thanks again
 
The major problem with monolithics (solid metal rather than conventional lead core, copper jacket) is that for a given weight their density is invariably less, making their overall length longer... which means they need a faster twist to stabilize properly.

Combine that with seating them deep to make them 'mag-length' compatible, loads need to be reduced for safety which only makes the situation worse.

So what's needed is either (maybe shorter) lighter-weight bullets than you'd otherwise be selecting, or a barrel with a faster-than-otherwise-needed twist rate.

Monolithics have been around for some time. Warner Tool Company (well-established iron sight maker and exceptional gunsmiths) introduced a line of monolithic target bullets late last year. Twists recommended are faster than what'd be appropriate for traditional bullets of similar weight. If that's followed they're very accurate.

In your 300WSM you may be able to use their 155's if your barrel's a 1:10 but even with that they'd be seated pretty deep for mag-length. Then there's the ethics and practicality of shooting with bullets that likely won't expand at all, making shot placement even more important.
 
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At least they LIKE being jumped. I typically find my best accuracy .050" - .080" off the lands. I had a Kimber 325 WSM and had to cut the throat .030" longer to find my sweet spot. I had best luck with straight TSX instead of tipped. Absolutely no terminal problems with either 165s or 168s in my '06 or Weatherby 300 on large elk out to 400 yds.. The LRX bullets are shorter for weight but pricey!
 
Use a lighter TSX or TTSX. As has been mentioned, the 130 will work very well. Don't worry about the lighter weight. For elk a 150 is heavy enough. Seat about 0.06" from rifling and they are very accurate. I've had good luck with RL17 and 130 gr TTSX in a .300WSM.
 

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