Replicating factory ammo performance

[J-B welder]

So that might be an odd thread title, given that reloaders tend to try to exceed factory ammo performance. But you folks seem like a friendly enough bunch from the lurking I've done so I figure you'd be willing to answer a question or two.

I have a new gun and I have found three makes of premium factory ammo that will shoot 0.75" groups or better at 100 yards. I'd like to practice with ammo that shoots that well, but I don't want to pay premium ammo prices to do it. I don't see any point in practicing with cheapo cartridges that shoot like crap out of my gun.

If I were to try reloading in order to be able to shoot more practice rounds for the same amount of money as buying factory fodder, choosing the bullet seems obvious, as I know of three that perform well in my gun. I've already shot four boxes of ammo just breaking the barrel in, zeroing the rifle and testing out different brands, so I have brass. The big mystery to me is powder. As long as I match the muzzle velocity of the factory ammo will any appropriate powder do? I'm guessing not. Can I just choose from the powders I've seen recommended and do a workup until I get the accuracy I'm looking for? I'd rather not buy a pound each of five kinds of powder just to find one that works well, although I'm sure I could find someone to take the other four off my hands.

Thanks for any thoughts you might be willing to offer.

 

[dok7mm]

What cartridge and bullet are you shooting? That will determine the proper powder.

Velocity and seating depth should improve grouping, if your rifle is capable.

 

[J-B welder]

.243 Win.

Sierra TGK 90 gr, Federal Berger Hybrid Hunter 95 gr and Barnes Vor-tx TTSX 80 gr all shoot well. Sierra is best at 0.5" @ 100 yards.

 

[dok7mm]

IMR-4350 worked very well for 85-90 gr bullets in years past, but I would look at StaBALL, Hybrid-100V or H-4831 if I was shooting a .243 today. The staBALL would be my first choice.

 

[Stammster]

1.) Buy a chronograph
2.) Measure fps of factory loads that shoot well
3.) Find a suitable powder(s) to match that velocity (manuals, online, etc), and load a ladder to verify over chronograph. You can also pull the factory bullet and measure the powder grains and look at the powder. Might be able to find out what they are using, or at least get close.
4.) Keep same COAL for handload as factory -for each respective bullet.

 

[J-B welder]

Thanks, fellas. I figured I'd have to keep the COAL the same as factory for each, at least to start in order to eliminate that variable.

Question on velocities: Recognizing the answer is really "it depends," how much difference in accuracy can the change in velocity make? If I'm 150 fps off the factory loads, how much difference could that make? A full MOA?

 

[Stammster]

150 fps is approx 2-4 grains charge weight difference, depending on cartridge.

It's not uncommon to see a 0.75 MOA group got to > 2 MOA over that range. Expect a POI shift also.

 

[JMW67]

.243 Win.

Sierra TGK 90 gr, Federal Berger Hybrid Hunter 95 gr and Barnes Vor-tx TTSX 80 gr all shoot well. Sierra is best at 0.5" @ 100 yards.

if you can find the 85gr. sierra hpgk they usually shoot lights out I would try hybrid 100v or h-4350 seat bullet 20 thou off the lands and I bet they shoot as good or better than any of the factory offerings great hunting bullet also

 

[J-B welder]

150 fps is approx 2-4 grains charge weight difference, depending on cartridge.

It's not uncommon to see a 0.75 MOA group got to > 2 MOA over that range. Expect a POI shift also.

Hmmmm.....so just getting in the ballpark probably ain't gonna be good enough to accomplish my goal.

How important is actually knowing the velocity? I mean, if I start at the starting charge and work my way up to max and see where I get the best accuracy, do I really care if I'm matching the factory velocity? Obviously it would take more time to do it that way. Is the chrono just to get me close and avoid having to load a whole bunch of cartridges that aren't going to shoot as well?

 

[Deleted member 107796]

You are starting with 2 excellent bullets, the Barnes TTSX and Berger Hybrid hunter. There is a wealth of online reloading data for these loads, as a starting point.

 

[JMW67]

If you do try the staball 6.5 be careful when you near max loads it tends to over pressure with small powder increases

 

[Stammster]

Hmmmm.....so just getting in the ballpark probably ain't gonna be good enough to accomplish my goal.

How important is actually knowing the velocity? I mean, if I start at the starting charge and work my way up to max and see where I get the best accuracy, do I really care if I'm matching the factory velocity? Obviously it would take more time to do it that way. Is the chrono just to get me close and avoid having to load a whole bunch of cartridges that aren't going to shoot as well?

If you don't have velocity to try to match, then you are going have to run a charge ladder around what you think is going to give you the required velocity... and see what shoots best. I suggest 3 shots at 0.3 gr increments to see group size and then whatever looks best, see if it repeats.

 

[basinman]

Nosler lists which powder was the most accurate in their loading data. That might help you narrow it down but might also be different for your rifle. Try to find reviews for reloading for your caliber and rifle. These are just a couple of quick suggestions.

 

[jdyoung]

What I do:

I always use factory rounds in newly acquired firearms, whether used or new. That way you are not breaking any Mfg. or previous owners rules in case it doesn't measure up.

Measure those factory rounds and also get velocity when testing. Once I find the accuracy I want, 5 loaded rounds are sacrificed by pulling the bullets and weighing the powder charges and bullets. Once I know the charge weight, I enter the data ( caliber, case volume, bullet: COAL, bullet brand -weight-seating depth, velocity , charge weight etc), into QuickLOAD. With all those in the program, and the powder charge weight entered, I just change the powder brand and designation until the velocity I have recorded is shown. Now I don't always get the very same velocity but I pick within 40 -50 fps of the velocity I recorded for the accurate factory rounds. Crimp is not included in QuickLOAD 's calculations, but is a factor in factory rounds, so I use a Lee Factory Crimp Die with an inch lb torque wrench setup on the press to vary the amount of crimp applied.