How much change should one expect.

[Savage Fanatic]

Through the summer I have been shooting 46gr. of BL-C(2) behind a 168gr Custom Competition HPBT, using Federal 210M primers, Federal .308GM brass, from a Savage 10FP-LE2B. Mostly for the Cornhusker State Games, and training leading up to it.

Over the course of this summer I received a invitation from a friend to go deer hunting with him, in the northwestern, i.e. panhandle part of the state. But he stated that I better prepare my self, and that hunting out here is not like sitting in a treestand and waiting for your target to come with in "your" desired range.

So I have been doing some research and talking with him. Via his advise and by what my rifle is currently is zeroed for, he believes that I should stick with the same load perimeters with the exception of changing to a 165gr Ballistic tip. The major thing that I am trying to figure out while waiting for various supplies to arrive, is how much of a change in the POI will there be between the 168gr HPBT and the 165gr BST, at both 100yds and 200yds?

 

[NOSLER]

Your change will be as follows.


168 HPBT let's say 2600fps zero at 100

0 2600fps -1.5
100 2413fps 0.0
200 2234fps -4.5
300 2062fps -16.0
400 1898fps -35.5


165 BT 2600fps

0 2600fps -1.5
100 2416fps 0.0
200 2240fps -4.5
300 2072fps -15.9
400 1910fps -35.3

The difference is very slim. If you want a bit more, go with the BST 168grain. .490 BC

168 BST

0 2600fps -1.5
100 2420fps 0.0
200 2248fps -4.5
300 2083fps -15.9
400 1924fps -35.0

Once again you are getting about a .5" at 400yards.

No real difference.

 

[Savage Fanatic]

:shock: :shock:

Just a minute, so I can get my self picked up off the floor.



I figured that they would be "close", meaning 1" to 1.5" at 200yds or so, but I never guessed that both a 165gr Ballistic Tip and a 168gr HPBT would be with in .5" or less at 400yds.

 

[NOSLER]

Since the 168 is better suited for 600 yards and beyond, the difference is little.

Until you see it on paper, most don't believe it.

 

[Savage Fanatic]

Since the 168 is better suited for 600 yards and beyond

But do have to say since most home grown (nebraskan) hunters don't know what it is like to shoot past the mail box at the end of their driveway.

Every rifle range that is built here in the eastern part of the state doesn't go past 200yds. Which makes it difficult for the annual CSG's to put any challange to the meet. But I have stated many times that I would like to see them add both a 500meter and 1000meter benchrest to the meet.

Now I can honestly say I have found the sweetspot.

 

[NOSLER]

I forgot to mention about the 168. That is a match bullet. While the BT is a hunting bullet......also used in matches.

 

[the444shooter]

Just make sure to clean your bbl when switching to a different bullet with different jacket material (assuming the 168's were sierra, or some other manufacture besides nosler) Even if they are the J4 from Nosler, I think the J4 has a different jacket material than the Partitions and Ballistic tips...NOSLER will have to correct me if I'm wrong. I have had some interesting groups when switching from bullet to bullet without cleaning my bbl. The most erratic groups were when I switched from the 165 Ballistic Tip to the 168 Barnes XLC...the XLCs grouped about 3" left and 2" higher than the Noslers. So, just something to consider when changing your bullets.

 

[Savage Fanatic]

Your change will be as follows.


168 HPBT let's say 2600fps zero at 100

0 2600fps -1.5
100 2413fps 0.0
200 2234fps -4.5
300 2062fps -16.0
400 1898fps -35.5


165 BT 2600fps

0 2600fps -1.5
100 2416fps 0.0
200 2240fps -4.5
300 2072fps -15.9
400 1910fps -35.3

The difference is very slim. If you want a bit more, go with the BST 168grain. .490 BC

168 BST

0 2600fps -1.5
100 2420fps 0.0
200 2248fps -4.5
300 2083fps -15.9
400 1924fps -35.0

Once again you are getting about a .5" at 400yards.

No real difference.

Thinking about this tonight, brought me to ask. Is there some sort of computer software or mathmatical formula that is available for figuring equasions of this nature? I know Federal has a downloadable catalog covering their products, but me personally I frown upon Federal's commercially loaded cartridges. After the headaches I went through getting my .300 Winchester Mag sighted in.

I started off with Winchester Supreme 150gr "Fail Safe's" (commercially loaded) which in my opinion they worked out great. But going by a rule of thumb that I read in several reloading manuals including "noslers" that when there is flattened primers, that is a sign of excessive pressure. So I went with a product from Federal's line-up (in which I don't recall) First shot out, not a thing. Same with second and third, so I had my brother pull off a couple rounds and come to find out that this product from Federal was falling about fifty feet short of its intended target. :roll:

 

[NOSLER]

In the back of our reloading manual there is a ballistics chart.

We also use RCBS's program and it comes in VERY handy while proofing loads.