Result from new Tikka hunting rifle/ trip and cartridge question

[sabrecross03]

Got to go hunting with a buddy in San Angelo a couple of days ago. I shot the 8-point buck with my new Tikka T3 Lite .308 Win equipped with a Nikon Buckmaster 4.5x14x40 SF scope. The buck was about 130 yards away. The cartridge was composed of 45 grains of Varget, a Hornady .308 Win 165 gr SST bullet, Winchester brass and primer, and I seated the bullet @ 2.755"

http://i1202.photobucket.com/albums/bb374/Roger_Benimoff/IMAG0555-1.jpg

I am disappointed with the muzzle velocity of the hand loads. I shot at targets with hand loads and factory loads @ 300 yds. With similar wind conditions I shot the following:

Factory load: Hornady super performance .308 Win, 165 gr SST catridges

Hand Load: 45 gr Varget, a Hornady .308 Win 165 gr SST bullet, Winchester brass and primer, and I seated the bullet @ 2.755" (sources used- Varget load data chart and Hornady Load data chart)

Results at 300yd: Factory rounds (2840 fps) consistently dropped approximately 6"
Hand loads (? fps) consistently dropped approximately 16" :shock:

I guess I'll need to adjust the hand-loads a bit...

[waksupi]

Use cast boolits!

Nice deer, though!

;o)

[Brithunter]

Without chronographing your hand loads how can you say they are too slow?

You might just have hit a low node and the bullets are exiting the muzzle on the down point of the swing. Plus the bullets shape might make a difference to the flight path. You need to check the bullets trajectory and see how it's shooting and check velocity before you caompare the factory loading and the hand load fairly.

[sabrecross03]

I shot 20 rounds of each (factory and hand loaded) and I was going by that. I am about to order a chrono so I can be a little more scientific about it.


Without chronographing your hand loads how can you say they are too slow?

You might just have hit a low node and the bullets are exiting the muzzle on the down point of the swing. Plus the bullets shape might make a difference to the flight path. You need to check the bullets trajectory and see how it's shooting and check velocity before you caompare the factory loading and the hand load fairly.

[Brithunter]

Good idea and one I need to follow as everytime I get sett o get a chronograph something else comes along. I can borrow one from time to time but really need my own.

I don't fully understand the OBT theory but if the bullet leaves the muzzle at the low point in it's movement then that shot will strike lower than one which leaves at the high point. Some rifles also spit bullets of different profiles and weights to quite different points on the target. Your may just be like that?

[NickSS]

First it is very unlikely that your factory ammo is giving you full factory velocity in your rifle. Second I have shot many loads in 308 rifles and that round is extremely easy to get good accuracy out of with almost any medium speed powder as for velocity only a chronograph will tell the tail. Thirdly the deer died and from the looks of it died fast so what's the problem. Believe me a deer will never be able to tell the difference between a bullet going 2600 fps from one going 3000 fps. The only difference you will notice is more bloodshot meatwith the higher velocity.

[sabrecross03]

I agree with your comments. My concern is the bullet drop at 300 yds. Whatever the fps of the factory verses hand-loaded ammo, my hand-loaded ammo drops (on average) an additional 10" over the factory ammo at 300 yds. (The factory ammo only drop 6 inches at 300 yds.)

I do not think that a 10" drop over the factory ammo is acceptable. I'd like to close the drop gap between the two but I am almost at the powder load limit with the Varget powder.


First it is very unlikely that your factory ammo is giving you full factory velocity in your rifle. Second I have shot many loads in 308 rifles and that round is extremely easy to get good accuracy out of with almost any medium speed powder as for velocity only a chronograph will tell the tail. Thirdly the deer died and from the looks of it died fast so what's the problem. Believe me a deer will never be able to tell the difference between a bullet going 2600 fps from one going 3000 fps. The only difference you will notice is more bloodshot meatwith the higher velocity.

[HollowPoint]

I love those Tikka's.

If I were limited to just one off-the-rack brand of rifle to buy, it would be a Tikka. Fortunately I'm not but, they are excellent rifles.

Incidently; I don't think that the velocity of your projectiles made any difference to that deer you shot. I used to chase after the highest safe velocity I could get. As the aging process set in, I slowly gravitated toward the accuracy rather than velocity. Of course, it's always good when you can have both but, again, now days I'll opt for accuracy over velocity.

Well done Sir.

HollowPoint

[sabrecross03]

Yeah, I don't think the deer knew the difference between the cartridges. The Hand-loaded round did it's job!I definitely want to find the sweat spot between accuracy and velocity. Santa bought me a Chrony Master Alpha Chronograph for Xmas. Let the fun begin!

[W.R.Buchanan]

Roger: My RGS77 with a 16.5 barrel and loads similar to yours produced what appeared to be higher velocity than the Federal Factory ammo, which is also listed at 2820fps. I would think your Hornady stuff should be more like 2900 fps even with the 165gr bullet.

45 gr of IMR 4895 with a 147gr recycled M80 ball bullets produced 2790 ish +/-10. The Federal American Eagle factory,,($10.95/box at the gun show), produced 2720 fps

Both of these were phoney readings as that is what they should have produced in a 24" barrel. The fact that my loads were dead on the elevation corrections given by a calculator for 2600 fps (which is what I expected to see) Indicated that the velocity was closer to 2600 than 2800.

Do beware as I have the exact same Chrony as you. They are sensitive to light reflections. I think the fix is to hang a white tee shirt over the top of the screens to stop reflections. I haven't gotten to verify this yet but am pretty confident it will work. I got those odd readings on a bright sunny day with bright shiney bullets.

With a 200 yard zero, and figuring 2600 fps. My elevation corrections are +.5 minute (2 clicks) for 200meters (220yds), +4.0 for 300 meters (330yds), +7.5 for 385 meters (420 yds) and 12.75 for 500 meters (550yds) These are my silhoutte target ranges but they would be similar to what you are trying to accomplish. Note: 4.0 MOA on the scope for 330 yds actually is @ +12.5" at the target distance.

Here is a link to the calculator I used and it is simple and easy to use. http://www.handloads.com/calc/

I ran the calc for 200yds, then each of the four other distances, and noted the difference between the new distance and the 200 yard zero. That number divided by the distance in 100 yard increments equals what you dial into your scope. It works well.

Try this out for each of your working loads once you have settled on them. Set up for a 200 yard base zero for your most commonly shot load, and then note all of the corrections for other loads to come to a usable zero without changing the original zero. That way you never have to change the original zero you just dial in the changes for each other load, and go back to zero when done.

Some call this "Mechanical Zero" and everything else comes off mechanical zero.

My loads follow these corrections like they are on a string!, which leads me to believe they are going the speed I think they are regardless of what my Chrony says. I will revisit this on an overcast day and see if it says differently, and if not then I will verify it by shooting across another chrono.

The only way to actually verify all of this is to shoot at the other distances, and make sure the bullets are going where you thought they were supposed to go. The ballistic calculator is strictly "theoretical" and must be verified by real world testing. I just got lucky and got mine right the first time.

I watch guys at everyone of my silhoutte shoots "Chasing the sights around" It is a complete waste of ammo, as they are trying to do it offhand! I personally am not that good.

With the gun actually doing what you think it is doing, and actually shooting where you want. It becomes a matter of you shooting the gun, as opposed to praying for divine intervention.

Nice deer, are you in CA?

Randy

[sabrecross03]

Wow, Santa must have had quite a selection because I finally got a Crony Beta Master!


Yeah, I don't think the deer knew the difference between the cartridges. The Hand-loaded round did it's job!I definitely want to find the sweat spot between accuracy and velocity. Santa bought me a Chrony Master Alpha Chronograph for Xmas. Let the fun begin!