30 cal ballistic comparison

About to test some 30cal loads tomorrow, to dial in a new Scope.

Always had good luck with this free program:

http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi

Just bought a First Focal Plane 4-20X Mildot scope.

personally I'm more familiar with MOA, doesn't really matter, I'm only using the mildots as holdover points.

3.47 MOA = 1 Mil. (can round up to 3.5 moa per mil)

Scope has 4 mildots.

My Standard 30'06 load is: 175grn Sierra matchking .505 BC @ 2950fps. (chrono'd)

Using the JBM program I get a scale out to 600 yards like this:

Little off center, but notice the drop at 600 yards says 10.3 MOA worth.

It's important when you do a calculation off a program like this to "true it" to the real world.

To true this scale you would need to Start with a 200 yard zero'd, rifle. Dial up 10.3 moa, shoot it at a real 600 yards distance and see if the zero from the program matches.

If it doesn't, you need to record the real-world dope, and go play with the inputs on the program till they match the real dope at 600. After that the closer stuff is usually lined up.

Depending on the time of year, sometimes my rifle matches the above scale exactly, other times it's 1/2 moa off. Clearly better than just a guess, though.

Note the Ft/lbs of energy at 600, 1446-lbs. Pretty good smack-down.

Dividing the 10.3MOA by 3.47 (3.47moa= 1mil) gives 2.96 so basically 3 mildots holdover for 600 yards.

Pretty good load, recoil not as bad as a 300 win mag, but certainly more than a 308, (most store bought 308 ammo with a 175grn bullet is like 2700fps.)

Tomorrow I wanna try a lighter alternative load using 150-155grn bullets.

58grns of N160 is what I use to get the 175s at 2950, so with the lighter bullets I'm going with 59grns.

Haven't chrono'd but I did a chart guessing 3090fps as the speed for 150grn Nosler Ballistic tip:

here's another using a 155grn Sierra matchking, (palma)

Interesting enough to get similar drop rates to the 150s, with a Lighter 125grn Bullet you have to push the velocity to 3290fps.

That would take a 300 Win Mag to do that.

With a 125grn bullet at the Speed of 3090fps, (what we chrono'd my then 308 with) It shows:

Not as flat over distance, and with Considerably less Energy delivered.

The 150grn range seems to be good balance of numbers.

Will see how accurate they prove tomorrow.

If you've made it this far, here's a pretty swell stock made in Norway sold by Kelby's for around $690

http://www.grsriflestocks.com/grodas/action-inlets

http://bulletin.accurateshooter.com/2013/01/kelblys-unveils-kts-stock-1-8x24mm-march-and-grs-stocks/



Finally, here's a Ho in a bikini:

 

I'm curious how a 40gr bullet and also a 250gr bullet would perform, using the same methods.

Thanks in advance.

 

45grn, (.224 caliber) guessing at some of the specifics, and using 3200fps

Paste de-formats everything.

Sierra makes a 240grn matchking in 30 cal.
https://www.sierrabullets.com/store/product.cfm/sn/9245/308-dia-240-gr-HPBT-MatchKing-box-of-500

Assuming 2300fps, and .711 for it's BC.

Rather a Bloop Gun.

Boost velocity to say 2700fps.

Still not as flat.

3000fps

2707ft-lbs of energy.


1st time I shot a 1000 yard match I used the JBM link to get an estimated zero.

I had a 100 yard zero, but had no clue how much to come up for 1000.

26.5-27 MOA was the answer. Wouldn't have hit the target frame without that.

At the same match there was a guy shooting a 7mm Mag, with 180grn Berger VLDs. I asked him his dope, he said 19MOA.

For a second, I thought, Hell I'm only 7 minutes off that with my 06! Then I did remembered, 1 moa = 10.(something) at 1000 yards, so 70 inches!

Plus too, after all this bullshit decoding, you still have to the read the wind, mirage, and make the shot!

 

Shit I was just kidding, you didn't have to do that.

I forgot the 40gr bullet for a .30 is a .224 with sabot. I think a 110gr is the lightest in .30.

Barnes used to make a 250gr .30.

 

JBM saves the previous visit, no big deal, (Yes it's slow at work today)

I can see why people are going to those Horus Reticles, or some of the others that extrapolate between mildots. Flatter shooting loads can leave you hanging in between.

 

Do the unlimited Robogun bench shooters use calculations, or do they just figure it out by experimentation?

 

is that a rem 700 action?

30/06 is something i never got into i have a 308 and 300wm but those are decent ballistics what kind of groups do you get?

 

Combo of Both is my guess.

 

It's impressive how close the calculations were for you. Cool stuff.

 

In the pic? Looks like it, or a clone.

With my standard 175grn load I got 1.65 inch group at 300 yards.

I'll see how these 150 Noslers, and 155grn palmas do tomorrow @ 100.

(if they're good I'll post pics, if not, I'll fail to mention it!)

I was going to build a separate rifle with a 13 twist barrel, but then I decided just to try them in the 10 twist gun I already have.

 

post the result either way I wonder if the lighter bullets will stabilize at 100 yards but 1.65 at 300 yards is nuts what rig are you running?

 

The Key is Truing the results. You could certainly miss using just the numbers, shooting beyond 350 yards.

 

This thing:


It's 1947 Winchester Model 70. It's got a big ass laminated stock, I paid way too much for, ($1200), a 26 inch Krieger Barrel with a near tight neck chamber, Burris 6-24X Euro Black Diamond Target Scope.


I just bought a new scope to try, and found an old time Pre-64 Winchester Target Stock on ebay, (only $110). I'm going to try it for a while (once I get it bedded to this action), Cause I won't care if it gets bumped varmint hunting.

 

Sexy not a bush gun that is for sure harris bipod? Did you build the rifle for target purpose or hunting?

 

I wanted it it for both, so it's on the heavy side.

Some brand-X bipod. That stock doesn't handle well off a bipod, it jumps straight up. Off a bag, or some soft rest, or with a sling it's great, though.

Stock has a rail for sling stops. it's around 17lbs with the expensive stock, it'll be 15 with the new used ebay stock. Still a pig buy hunting standards.

The note card on the first pic are the dial up notes for the target scope. It works, but it's old style. The gun's old style though.

Here's another one of my junkers before I sold it to a buddy of mine.

http://forums.sherdog.com/forums/f65/tubegun-rifle-report-nighttime-critter-hunt-2603605/

 

its nice i love that huge haul for one night but i never bought any AR rifles since i live in Canada and restricted rifles are not allowed for hunting but my newest buy was a T97 Chinese bullpup and its really nice since it is classified non restricted which means it can be taken to the bush. Don't ask me to explain the gun laws of Canada it does not even make sense.

 

Weather was hot today.

Started by Chronoing my standard 175grn load. Previously it clocked at 2950, today it was 2909fps.

The two rounds I tested were:



155grn Sierra matchking, (palma) clocked at 2990fps.

150grn Nosler Ballistic tip Clocked at 3080fps

I'm rather a shit bench shooter, I never use a proper setup, but always this sort of thing:





It easy to see-saw the group with no rear bag, but on the other hand, I always felt, whatever accuracy I achieved like that was bound to be closer to what i get in the field, than any benched up, locked down setup.

Conditions were sun and clouds and clouds and sun, and boiling mirage. the temp climbed from 85 to 93 degrees in the 45 minutes I was there.

I had 10rnds. of each load, and 5 of my 175grn control load.

Between the chrono not reading, and zeroing while trying to shoot groups I ened up running out of the 150s.

Here's the 1st group with the 155 Palmas:



End up with only 4 shots to test the 150s, and ended up see sawing the group downward. No excuses, just shit shooting.



I think they'll be accurate too though, I'll try them at another time.

I totally pooched the 2nd group with the Palmas as well:



Gun liked the Palmas, with their heavy jackets they should do well on long range hogs.

I liked the speed of the 150s, I wish the 155s would've broken 3000fps.

Now to re-enter these numbers in the ballistics program to see what it says on the drop out to 600.