slow barrel

so I have a browning xbolt speed LR 6.5 prc with 26" barrel. I was verifying my dope without shooting through a chrono. I haven't shot through a chrono because I don't have one, and I dont live close to anyone that does. I zeroed my rifle at 200, made sure my scope height was correctly plugged into my 2 shooting apps that I use (Shooter and Hornady), and then entered the muzzle velocity that was listed on the boxes. (Hornady ELDX and Berger 156 EOL). At 500 yards I was grouping low with both bullets. When I plug in the numbers to the mv to get my dope matching my point of impact im about 200-250fps slow with each ammo type. Im somewhere around 2750 with the Bergers and 2850 with the Hornadys. I know this isn't the best and most precise way to build a dope card, but it has worked well for me in the past. How much is not knowing actually velocity actually hurting my accuracy? This is a hunting rifle only. Any ideas here? Barrel sound really slow? Am I missing something. On the apps that I use I made sure that scope height, G7 BC's, all environmental factors etc are correct. Maybe BC's arent true?

I doubt you have a slow barrel. It's just likely the box velocities are over exaggerated, or shot in warm weather with a 30" test barrel and so on an so forth. Hornady is pretty spot on with their listed BCs.

You don't need a chrono if you are drop testing the ammo to the ranges you intend to hunt. Where those bullets hit is what you record for your range card.

Make sure you are using station pressure and not the local weather station pressure report. There can be a big difference there.

I'm ready to sell my magnetospeed v3. Send me a check for $125 and you'll have your very own chronograph.
I don't think you can trust velocities from manufacturers, have to verify. It will take less ammo to verify drops if you know how fast your gun is flingin bullets.
Shoot a pm if you're interested in my chronograph.

Wingnut00 said:

I'm ready to sell my magnetospeed v3. Send me a check for $125 and you'll have your very own chronograph.
I don't think you can trust velocities from manufacturers, have to verify. It will take less ammo to verify drops if you know how fast your gun is flingin bullets.
Shoot a pm if you're interested in my chronograph

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with the number of people moving to the newer chronos you're in the golden age of buying a good working chrono for very little money used

Well, an interesting subject.

In my experience there are "slow" barrels. There are guns that are "slow" until the barrel breaks in a little.

but

More often, the rating on the box is way off.

Your method of getting your dope without a chrono is fine and you seem to be doing it "right".

IMO: If you can spare it get the used Magnetospeed offered.

Wingnut00 said:

I'm ready to sell my magnetospeed v3. Send me a check for $125 and you'll have your very own chronograph.
I don't think you can trust velocities from manufacturers, have to verify. It will take less ammo to verify drops if you know how fast your gun is flingin bullets.
Shoot a pm if you're interested in my chronograph.

Click to expand...

Yea, I'll take it. do you have paypal? for some reason I cant send a pm.

Is it a new barrel?

kylcan2510 said:

Yea, I'll take it. do you have paypal? for some reason I cant send a pm.

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I'll try to send ya a pm. Give me a minute

Ah you ain't got enough messages for personal messages, think you got to have 10. Are you comfortable giving me your phone number on this thread? If so spell it out, don't just put your number on here.

Your factory ammunition sounds like it is slower than what is marked on the box

As long as you are doing your part targets don't lie, it's nice to have a chrono too

kylcan2510 said:

Five zero five- two six three- three four four three

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Ok! I'll shoot a text your way in the morning to discuss details ok. Thank you

isn't that info on the box measured at ASL, 59* and 29.53 inHg?