savage 12fv 308 oal

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08-04-2018, 04:22 PM
69gen1

savage 12fv 308 oal

Just got the hrdy oal gauge, and the bullit comparator, and the cartridge headspace comparator. When I use the oal gauge with the hrdy 178 hpbt bullet I get readings of 2.870 within .03 +/- because of the tips. The ogive reading is 2.203 - 2.204". I am just sticking in the lands a tad bit but bullet does stick but easily comes out its not hammer tight. If I set my oal to book 2.800 that puts the ogive at 2.130. That's a .074 jump if I'm doing all this right which is taking up a lot of case space i think. I am using there modified case on the gauge but also using there headspace comparator it only shows like .003 less than my fired formed brass.

Next up is the hrdy 168 amax with an average 2.823 max oal and an ogive reading of 2.184 and 2.185 average over 5 projectiles which back to book spec of 2.800 that means I'm about .020 from lands. All this is new to me and I have not reloaded any rounds for this rifle it's only shot factory. I know ever bodies rifles are not the same so any info from you all is appreciated. What are you seeing with these bullets or am I not doing it right? Thanks to all!
08-04-2018, 04:59 PM
Ted_Feasel

Quote:

Originally Posted by 69gen1

Just got the hrdy oal gauge, and the bullit comparitor, and the cartridge headspace comparitor..when I use the oal gage with the hrdy 178 hpbt bullit I get readings of 2.870 withen .03 +- because of the tips .the ogive reading is 2.203 2.204 .I am just sticking in the lands a tad bit but bullit does stick but easily comes out its not hammer tight. if I set my oal to book 2.800 that puts the ogive at 2.130..that's a .074 jump if I'm doing all this right .which is takeing up a lot of case space i think..i am useing there modified case on the gauge but also useing there headspace comparitor it only shows like .003 less than my fired formed brass.next up is the hrdy 168 amax withe a average 2.823 max oal with a ogive reading of 2.184 and 2.185 average over 5 projectials which back to book spec of 2.800 that means I'm about .020 from lands...all this is new to me and I have not reloaded any rds for this rifle it's only shot factory.i know ever bodies rifles are not the same .so any info from u all is appreciated what u all are seeing with these bullits or I'm not doing it right....thanks to all

That's wild the shilen barrel that I put on my Savage gives me virtually identical measurements that you typed out there and I ended up settling with just an overall length of 2.800 on the 178 grain Hornady ELD and that works perfectly. I played with jump space from .005 on out and I dont remember without looking at the paper I did all the math on but the jump spaced I ended with gave me 2.800 oal.

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08-04-2018, 05:14 PM
69gen1

Quote:

Originally Posted by Ted_Feasel

That's wild the shilen barrel that I put on my Savage gives me virtually identical measurements that you typed out there and I ended up settling with just an overall length of 2.800 on the 178 grain Hornady ELD and that works perfectly. I played with jump space from .005 on out and I dont remember without looking at the paper I did all the math on but the jump spaced I ended with gave me 2.800 oal.

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I have not reloaded any rds for this kinda confused with the readings from 178 hpbt and the 168 amax I know each Bullitt different but wow..when u just measure the the bullit it list like 1.345 +- .00 5 on the 178 and 1.277 on the 168 amax .both bullits share the same oal book start of 2.800
08-04-2018, 05:18 PM
Ted_Feasel

Quote:

Originally Posted by 69gen1

I have not reloaded any rds for this kinda confused with the readings from 178 hpbt and the 168 amax I know each Bullitt different but wow..when u just measure the the bullit it list like 1.345 +- .00 5 on the 178 and 1.277 on the 168 amax .both bullits share the same oal book start of 2.800

I own alot of savages and they all are very tight spec chambers, I imagine in part because of the way they set their headspace but I wouldn't be surprised if 2. 800 works great for you

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08-04-2018, 05:35 PM
69gen1

Quote:

Originally Posted by Ted_Feasel

I own alot of savages and they all are very tight spec chambers, I imagine in part because of the way they set their headspace but I wouldn't be surprised if 2. 800 works great for you

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Looking at the math it's a drastic swing from the 168 to 178 hpbt guess because it's about .068 longer than the 168 amax and about .020 diff in ogive placement so I assume set it at 2.800 and work up..the 178 case is going to have some case powder shrinkage and pressure I think. I don't know what that blind mag in the fv will except on oal I've shot the gold medal 175 sie. match in it and the are around 2.800 to 2.805 oal.i according to the bullit comparitor there ogive measurement varied by .005 which suprised me for match they shot 3/4 to 1 with 3 togeather quite often on 5 rds. At 100..allways has the kickers me or it..probably 50 50..
08-05-2018, 06:14 AM
rjtfroggy

Just remember that 2.800 is a factory safe ( lawyer) for all Sammi speced chambers and I would almost bet no 2 are the same.
As an example I have two 308 barrels. 1 measures out at 3.07 the other 2.275 one is factory the other custom, which is right.
Load to your own measurements and go from there.
08-05-2018, 06:34 AM
69gen1

Quote:

Originally Posted by rjtfroggy

Just remember that 2.800 is a factory safe ( lawyer) for all Sammi speced chambers and I would almost bet no 2 are the same.
As an example I have two 308 barrels. 1 measures out at 3.07 the other 2.275 one is factory the other custom, which is right.
Load to your own measurements and go from there.

what is confusing to me is the 178 hpbt setting that rd at the 2.800 was showing a .074 jump compared to the 168 amax at 2.800 with .022 jump..just curious what others was useing as the oal . 178 looks like it's got lots of play room in the oal. Compared to the 168 in my rifle
08-16-2018, 10:08 AM
Texas10

What is happening here is the fact that the gage you are using to measure CBTO is not an exact replica of your chamber/throat. It's just a convenient way to measure, so don't expect two different bullets to have the same CBTO or OAL at touch, and don't expect your gage to measure the same as someone else's. CBTO (Case Base To Ogive) is just a convenient starting point, as long as you can get repeatable measurements by whatever gage you use. As Froggy wrote, load to your own measurements and go from there.
08-19-2018, 01:50 PM
69gen1

Quote:

Originally Posted by Texas10

What is happening here is the fact that the gage you are using to measure CBTO is not an exact replica of your chamber/throat. It's just a convenient way to measure, so don't expect two different bullets to have the same CBTO or OAL at touch, and don't expect your gage to measure the same as someone else's. CBTO (Case Base To Ogive) is just a convenient starting point, as long as you can get repeatable measurements by whatever gage you use. As Froggy wrote, load to your own measurements and go from there.

That's great info Texas 10