Range Report .308 long range bullet options

[m1ajunkie]

Why do long range shooters prefer the heavier bullets in a caliber for long range shooting?

For example the 155 scenar (2600fps) with .508 BC is matching and barely beating out the 175smk (2500fps) out to 1000yds on velocity, energy, drop, and wind. I ran a comparison in JBM's calculator and the 155 is even supposed to beat the wind a little better. I have only shot 175smk's and 178 amax's out of my .308 at ranges out to 700yds, so I am just basing my idea of the 155 on data I have gathered from JBM. I used velocities I gathered using my handloads and chrony data.

I know people say the 155 scenar needs to be running faster, but that load shoots very well out of my 16" rifle.

 

[MEDICGORDO]

Re: .308 long range bullet options

If you shoot the 155's they need to be in the 2,900+ range thats where they will shine.I had really good luck out of 190 Bergers and never really messed with the 175's.I would shoot 155's to 800 and 190's past that.Used XBR WITH THE 155'S AND N550 for the 190's.Heavier bullets most of the time have a higher b/c even if they are slower at the muzzle, they will still retain more fps and energy at long range.For exampleI was loading 155's on second fired brass @ 1k and while working up a load,I wasn't hitting a damn thing.I shot them through a crono and did not realize it but they were @ 2,700 with varget.I'm pretty sure they were going sub sonic right at 950 or so.Loaded them with XBR got my fps up to 2,950 and what do you know they worked like a champ to 1k.The Berger still did better with a m/v of 2,750 @ 1k IMO and in my groups.

 

[Timo Turl]

Re: .308 long range bullet options

the 175 and 178 are being shot nearer to 2700 than 2500 i'd suggest for most

 

[KNIGHT11B4]

Re: .308 long range bullet options

A lot depends on whether you are using a round for an already built rifle or building a new rifle.

What I mean is if you already have lets say shorter barrel 308, you are better off with the 175. If you already have a longer barrel 308 with proper twist then you may see improvement with the 155.

If your building a new rifle then you have options to build geared towards one over the other.

I stick with the 175s, and they run great for me. Personally if I wanted to run lighter better BC rounds, Id build a new rifle.

 

[m1ajunkie]

Re: .308 long range bullet options

Knight,

I am using this round in a rifle I already have. I don't really have a need to switch rounds as the 175smk and 178amax are performing really well for me. I just decided to give the 155's a try and my first couple of load development groups they shot extremely well.

I got curious as to whether they would continue that accuracy past 200yds where I tested them.

 

[KNIGHT11B4]

Re: .308 long range bullet options

As already stated, the 155s need more velocity to be worth using. They may group well at 100, but out of a 16 inch I wouldnt count on them at distance.

Stick to the 175s and 178s.

 

[hank440]

Re: .308 long range bullet options

Knight is right,

I'm using the 155's out of a 26" bbl@2890 fps and they work great. Using them in a short barrel will probably not work as well.

 

[Briggs]

Re: .308 long range bullet options

I am running 155 smk palmas out of my 20" 5r and getting 2740 fps using 46.8 of target. I don't do a lot shooting past 600 but is that velocity about as good as can be expected out of that 20" barrel? I was starting to flatten primers around 47 grains.

 

[MitchAlsup]

Re: .308 long range bullet options

briggs: see my comments in the Reloading section.