308 Chamber seems small ?

Metal god · July 20, 2013, 01:23 AM

I'll start this thread by saying I have not reloaded anything before . I still do not have any powder so I was doing some measurements .

The rifle is a Savage model 10 FCP-K .308

I measured my chamber 2 different ways

1) I took a case that had just enough neck tension to hold the bullet . I put a 175gr smk in the case but just barely . I then put it in the rifle and closed the bolt . I then carefully removed the cartridge and measured the OAL . I did this 4 times and the OAL never got past 2.775 and 3 of the 4 were 2.750-ish

2 ) I closed the bolt on a empty chamber . I then pushed a cleaning rod down the bore till it stopped on the bolt . I then marked the rod where it stopped . I then removed the bolt and drooped 175gr smk bullet in to the chamber . I kept it pressed up against the lands with a dowel and pushed the cleaning rod back down the barrel till it stopped on the bullet . I then marked the cleaning rod where it stopped . That measurement is 2.745

Because I did it 2 different ways and the numbers came out pretty much the same . I'm guessing that measurement is correct .

My questions are

1 )Do you think those ways of measuring would be accurate ?

2 ) Is that a small chamber ? or is the COAL 2.800 a max and anything under is gtg . I find it odd that If I were to load a cartridge to spec from my Sierra book it would not fit in my rifle .

3 ) If it is small , what's the largest bullet I'll be able to shoot out of it ? I'm starting with 175s but was thin ling I would like to shoot 190s out of it at some point .

EDIT : I just relized something . depending on what bullet I put in there the measurements are going to change oops . The 178gr A-MAX are 2.805

so I guess I measure each bullet and just keep them a couple thousandths off the lands period or what .

Jimro · July 20, 2013, 01:52 AM

The chamber is fine, it is the throat you are worried about.

Do a normal load workup. The only time you want a longer (custom) throat is if you are working exclusively with long seated bullets to get the most powder room (Palma or F/TR Class).

Jimro

Metal god · July 20, 2013, 01:59 AM

yes , and thanks I'm new to the reloading part of firearms so I'm sure it will take me a bit to get the right wording down . I do know and or realize the chamber it self if fine I was worried that if I would have loaded the 175gr smk to 2.80 like the book says is OK it would have got stuck in the bore or pushed back into the case causing a pressure spike .

Jimro · July 20, 2013, 02:12 AM

You'll be fine if you start your load workup at 2.75 and stay there until you find your peak accuracy. Then you can start playing with seating depth, although Unclenick has a great way to do it the other way around (find optimal seating depth first).

Jimro

steve4102 · July 20, 2013, 09:30 AM

Your Savage has a very short throat. There are a lot of New Savage owners out there experiencing short throats with their 308.

One such owner even had his Short Throated Savage grab the bullet of Federal Factory ammo and pull it completely out of the case upon extraction.

IMO, if your rifle cannot handle an OAL at least equal to SAAMI max of 2.810 with any SP bullet( especially Factory ammo) it should be send it back to Savage to get it properly throated.

higgite · July 20, 2013, 11:10 AM

Yeah, that sounds like it's worth at least a conversation with Savage. FWIW, I have a 10FCP in .308Win that I measured to have 2.825" cartridge OAL to lands with a 168gr A-MAX. I used a Hornady OAL tool for measuring. That's the only bullet I've tried so far. I don't know how the profile of that bullet compares with the bullets you used, but the Hornady Handbook calls for their 168gr and 178gr A-MAXes to be seated to the same 2.80" OAL.

Brian Pfleuger · July 20, 2013, 11:21 AM

Do you have the Hornady Bullet Comparator set? That would tell you where the actual ogive of the bullet was stopping.

If you did, you could use it to compare the chamber to SAAMI spec.

If you don't have that tool, you might consider getting it. The main advantage is that it measures at the ogive, meaning that the bullet you use doesn't matter. The total OAL will change from bullet to bullet but you can always set the ogive at the length you want and it will always be the same distance from the rifling, which is what you really care about anyway. The point in space where the nose ends is of no concern.

The SMK is a bit on the short side for it's weight. JBM lists it at 1.240, while a 150gr Hornady SST is 1.203 and the 178gr A-Max is 1.318. I wouldn't be a bit surprised if the OAL for the SMK came out close to that difference (0.078 or so) shorter than the A-Max. No guarantee that ALL of that difference is between the ogive and tip but most of it should be.

I'll give you a third measurement method too. You might find it more accurate than the others (or maybe not

). Do what you did in the first example except don't use the bolt to chamber the cartridge. Push it in with your fingers and/or a piece of a dowel. Depending on how tight the bullet is in the case, you'll want to tap the case to make sure it's fully seated against datum point in the chamber. Then, use a cleaning rod or wooden dowel to very gently push the bullet out from the muzzle end. This ensures that the bullet sticking in the rifling isn't changing your OAL.

higgite · July 20, 2013, 12:14 PM

Further to what Brian said, the 168gr A-MAX that I referred to in post#6 measured 2.192" to the ogive with a Hornady comparator. That's at 2.825" OAL.

Metal god · July 20, 2013, 02:02 PM

Thanks for the reply"s . It seems a little mix on if it is an issue or not . I do plan on buying the gage's to get the exact measurements . I was thinking , in some ways a short throat/lead could be a good thing . As long as I know that is an issue and load appropriately I should be good . The possible good part is with a shorter throat the barrel should shoot accurately longer because it has more throat to erode before the barrel is trash . I've done a little research and have seen guys with the same bullet in there 700s have a OAL of 2.95 . I think I'd rather have the short throat rather then a long one . what say you guys ?

steve4102 · July 20, 2013, 04:02 PM

Here is another Savage owner that can't load to SAAMI spec due to a short throat, only this one is in 30-06.

http://www.thehighroad.org/showthread.php?t=722999

Dan Newberry · July 20, 2013, 04:38 PM

Savages are pretty notorious for short throats, which as you suspect can be a good thing if you know what you've got.

I would prefer that to the "ample as Bertha's bloomers" throat lengths Remington typically uses, for sure.

I did hear tell of the guy who said a Federal GMM load wouldn't chamber in his Savage, and he pulled the bullet out of the case when he tried to extract it. That seems a bit suspect to me, as the GMM ammo has some pretty stiff neck tension... I don't see how that would happen with a factory load at all (the bullet simply couldn't stick in the lands hard enough for that, I wouldn't think)... but with handloads, that's another story, and it does happen.

That throat will "dress forward" just a bit as the barrel breaks in. The leading edges of the lands will wear down after the first 100 or so shots, and your issue will be a non-issue.

Having a chamber with the lands that close will mean higher velocity with a given load recipe, so work your loads up from starting levels, and check by chronograph if you have one.

Dan

wvscotsman · July 21, 2013, 12:59 PM

A way I have found to measure the distance to where the ogive hits the lands is like this:

You need a case that matches the caliber you are using, a small diameter cleaning rod, your choice of bullet, dial calipers, a drill with a bit slightly bigger than the rod, and something like a mechanics pick to pull the case out.

1. Take the case and punch out the fired primer. Drill out the primer pocket so that the cleaning rod will go through back of the case.

2. You want the mouth with just enough pressure on the bullet to where it will move freely but not too easily. You want it to move but with a small amount of force. You will have to experiment with this till you get it to where you are comfortable.
3. Put the bullet you want to measure with in the case. Push it in to where it falls into the case to where the powder would normally be. NOTE: EVERY bullet will be different depending on shape and size and weight. You will need to do this with each different bullet you use.
4. Take the bolt out of your rifle, you wont need it for this method.
5. Push the case into the chamber with your hands until it is in fully.
6. Using the cleaning rod push the bullet out of the case until it meets resistance. Remove the rod.
7. Use the pick to pull the case out carefully. You dont want it to drop as that might push the bullet in further and distort your measurement.
8. Use the dial calipers to measure the overall case length. This is the length where the ogive hits the lands.

I used this method along with putting the case in using the bolt as you described earlier. I got the same measurement both times. I just like this method better it is less awkward for me.

thump_rrr · July 21, 2013, 01:18 PM

I have a Savage 10BA which has a chamber which is 0.005 shorter than SAAMI minimum spec. I could have sent it back in to have the barrel brought out a bit but it shoots so accurately that I'd regret it.
As long as you reload and know what you have that's not really an issue.

July 20, 2013, 01:23 AM	#1
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	308 Chamber seems small ? I'll start this thread by saying I have not reloaded anything before . I still do not have any powder so I was doing some measurements . The rifle is a Savage model 10 FCP-K .308 I measured my chamber 2 different ways 1) I took a case that had just enough neck tension to hold the bullet . I put a 175gr smk in the case but just barely . I then put it in the rifle and closed the bolt . I then carefully removed the cartridge and measured the OAL . I did this 4 times and the OAL never got past 2.775 and 3 of the 4 were 2.750-ish 2 ) I closed the bolt on a empty chamber . I then pushed a cleaning rod down the bore till it stopped on the bolt . I then marked the rod where it stopped . I then removed the bolt and drooped 175gr smk bullet in to the chamber . I kept it pressed up against the lands with a dowel and pushed the cleaning rod back down the barrel till it stopped on the bullet . I then marked the cleaning rod where it stopped . That measurement is 2.745 Because I did it 2 different ways and the numbers came out pretty much the same . I'm guessing that measurement is correct . My questions are 1 )Do you think those ways of measuring would be accurate ? 2 ) Is that a small chamber ? or is the COAL 2.800 a max and anything under is gtg . I find it odd that If I were to load a cartridge to spec from my Sierra book it would not fit in my rifle . 3 ) If it is small , what's the largest bullet I'll be able to shoot out of it ? I'm starting with 175s but was thin ling I would like to shoot 190s out of it at some point . EDIT : I just relized something . depending on what bullet I put in there the measurements are going to change oops . The 178gr A-MAX are 2.805 so I guess I measure each bullet and just keep them a couple thousandths off the lands period or what . Last edited by Metal god; July 20, 2013 at 01:51 AM.

July 20, 2013, 01:52 AM	#2
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	The chamber is fine, it is the throat you are worried about. Do a normal load workup. The only time you want a longer (custom) throat is if you are working exclusively with long seated bullets to get the most powder room (Palma or F/TR Class). Jimro __________________ Machine guns are awesome until you have to carry one.

July 20, 2013, 02:12 AM	#4
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	You'll be fine if you start your load workup at 2.75 and stay there until you find your peak accuracy. Then you can start playing with seating depth, although Unclenick has a great way to do it the other way around (find optimal seating depth first). Jimro __________________ Machine guns are awesome until you have to carry one.

July 20, 2013, 11:21 AM	#7
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Do you have the Hornady Bullet Comparator set? That would tell you where the actual ogive of the bullet was stopping. If you did, you could use it to compare the chamber to SAAMI spec. If you don't have that tool, you might consider getting it. The main advantage is that it measures at the ogive, meaning that the bullet you use doesn't matter. The total OAL will change from bullet to bullet but you can always set the ogive at the length you want and it will always be the same distance from the rifling, which is what you really care about anyway. The point in space where the nose ends is of no concern. The SMK is a bit on the short side for it's weight. JBM lists it at 1.240, while a 150gr Hornady SST is 1.203 and the 178gr A-Max is 1.318. I wouldn't be a bit surprised if the OAL for the SMK came out close to that difference (0.078 or so) shorter than the A-Max. No guarantee that ALL of that difference is between the ogive and tip but most of it should be. I'll give you a third measurement method too. You might find it more accurate than the others (or maybe not ). Do what you did in the first example except don't use the bolt to chamber the cartridge. Push it in with your fingers and/or a piece of a dowel. Depending on how tight the bullet is in the case, you'll want to tap the case to make sure it's fully seated against datum point in the chamber. Then, use a cleaning rod or wooden dowel to very gently push the bullet out from the muzzle end. This ensures that the bullet sticking in the rifling isn't changing your OAL. __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley

July 20, 2013, 04:38 PM	#11
Dan Newberry Senior Member Join Date: October 3, 2012 Location: Wytheville, VA Posts: 216	Savages are pretty notorious for short throats, which as you suspect can be a good thing if you know what you've got. I would prefer that to the "ample as Bertha's bloomers" throat lengths Remington typically uses, for sure. I did hear tell of the guy who said a Federal GMM load wouldn't chamber in his Savage, and he pulled the bullet out of the case when he tried to extract it. That seems a bit suspect to me, as the GMM ammo has some pretty stiff neck tension... I don't see how that would happen with a factory load at all (the bullet simply couldn't stick in the lands hard enough for that, I wouldn't think)... but with handloads, that's another story, and it does happen. That throat will "dress forward" just a bit as the barrel breaks in. The leading edges of the lands will wear down after the first 100 or so shots, and your issue will be a non-issue. Having a chamber with the lands that close will mean higher velocity with a given load recipe, so work your loads up from starting levels, and check by chronograph if you have one. Dan __________________ *www.BANGSTEEL.com* Practical Long Range Rifle Courses... Optimal Charge Weight handload consulting

July 20, 2013, 01:59 AM	#3
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	yes , and thanks I'm new to the reloading part of firearms so I'm sure it will take me a bit to get the right wording down . I do know and or realize the chamber it self if fine I was worried that if I would have loaded the 175gr smk to 2.80 like the book says is OK it would have got stuck in the bore or pushed back into the case causing a pressure spike .

July 20, 2013, 09:30 AM	#5
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	Your Savage has a very short throat. There are a lot of New Savage owners out there experiencing short throats with their 308. One such owner even had his Short Throated Savage grab the bullet of Federal Factory ammo and pull it completely out of the case upon extraction. IMO, if your rifle cannot handle an OAL at least equal to SAAMI max of 2.810 with any SP bullet( especially Factory ammo) it should be send it back to Savage to get it properly throated.

July 20, 2013, 11:10 AM	#6
higgite Senior Member Join Date: October 21, 2010 Posts: 1,025	Yeah, that sounds like it's worth at least a conversation with Savage. FWIW, I have a 10FCP in .308Win that I measured to have 2.825" cartridge OAL to lands with a 168gr A-MAX. I used a Hornady OAL tool for measuring. That's the only bullet I've tried so far. I don't know how the profile of that bullet compares with the bullets you used, but the Hornady Handbook calls for their 168gr and 178gr A-MAXes to be seated to the same 2.80" OAL.

July 20, 2013, 12:14 PM	#8
higgite Senior Member Join Date: October 21, 2010 Posts: 1,025	Further to what Brian said, the 168gr A-MAX that I referred to in post#6 measured 2.192" to the ogive with a Hornady comparator. That's at 2.825" OAL.

July 20, 2013, 02:02 PM	#9
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	Thanks for the reply"s . It seems a little mix on if it is an issue or not . I do plan on buying the gage's to get the exact measurements . I was thinking , in some ways a short throat/lead could be a good thing . As long as I know that is an issue and load appropriately I should be good . The possible good part is with a shorter throat the barrel should shoot accurately longer because it has more throat to erode before the barrel is trash . I've done a little research and have seen guys with the same bullet in there 700s have a OAL of 2.95 . I think I'd rather have the short throat rather then a long one . what say you guys ?

July 20, 2013, 04:02 PM	#10
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	Here is another Savage owner that can't load to SAAMI spec due to a short throat, only this one is in 30-06. http://www.thehighroad.org/showthread.php?t=722999

July 21, 2013, 12:59 PM	#12
wvscotsman Member Join Date: December 8, 2012 Posts: 17	A way I have found to measure the distance to where the ogive hits the lands is like this: You need a case that matches the caliber you are using, a small diameter cleaning rod, your choice of bullet, dial calipers, a drill with a bit slightly bigger than the rod, and something like a mechanics pick to pull the case out. 1. Take the case and punch out the fired primer. Drill out the primer pocket so that the cleaning rod will go through back of the case. 2. You want the mouth with just enough pressure on the bullet to where it will move freely but not too easily. You want it to move but with a small amount of force. You will have to experiment with this till you get it to where you are comfortable. 3. Put the bullet you want to measure with in the case. Push it in to where it falls into the case to where the powder would normally be. NOTE: EVERY bullet will be different depending on shape and size and weight. You will need to do this with each different bullet you use. 4. Take the bolt out of your rifle, you wont need it for this method. 5. Push the case into the chamber with your hands until it is in fully. 6. Using the cleaning rod push the bullet out of the case until it meets resistance. Remove the rod. 7. Use the pick to pull the case out carefully. You dont want it to drop as that might push the bullet in further and distort your measurement. 8. Use the dial calipers to measure the overall case length. This is the length where the ogive hits the lands. I used this method along with putting the case in using the bolt as you described earlier. I got the same measurement both times. I just like this method better it is less awkward for me. __________________ Savage Model 11 VT 308 Heavy Barrel. Savage Model 93F 22LR

July 21, 2013, 01:18 PM	#13
thump_rrr Senior Member Join Date: October 12, 2010 Posts: 403	I have a Savage 10BA which has a chamber which is 0.005 shorter than SAAMI minimum spec. I could have sent it back in to have the barrel brought out a bit but it shoots so accurately that I'd regret it. As long as you reload and know what you have that's not really an issue.