Minimum Freebore for 215 Berger

[gsg5pk]

What is the minimum freebore to shoot 215 Berger in .308 win


Do 2013 US FTR chamber was enough? (.343nk, 170fb, 1-30)

 

[jamesl]

I use 215's out of a .168fb and have shot well with them but I would say that is the min. I am shooting 10 off the lands and the boattail jucture is just barely above the neck/shoulder juncture. A .200-.220 would be better.

James

 

[XTR]

What is the minimum freebore to shoot 215 Berger in .308 win


Do 2013 US FTR chamber was enough? (.343nk, 170fb, 1-30)

Laurie has a long post in here somewhere about seating depths for the 185/200/215 bergers.

Take this for what it's worth, free intenet advice. Don't bother with the 215s in a rifle throated for the 185s.

My base to ogive touching the lands with a 185 Jugg shooting in a 2013 FTR with a .168 FB is ~2.335 with a Hornady tool.

My base to ogive in one of my barrels that i have throated at what consider barely adequate for the 215s is 2.420, that barrel also works with the 200s. If I was thorating solely for the 215s it would probably be closer to 2.50 as the bearing surface is just above the junction in that chamber. I can't check the measurement for the 185s in that barrel, they fall out of the case.

In addition you are going to be taking a big chunk of case space with the tail of the bullet.

I know, you've run the numbers on JBM and if you can get them fast enough they will shoot inside of the 185s or the 200s, so armed with this information you can buy 100 and see. Good luck, but my personal opinion is that if it's not set up for it it is a waste of time. You will be better off shooting the 185s. This does not even get into the recoil management issues most folks (myself included) have with the 215s.

 

[gsg5pk]

I use 215's out of a .168fb and have shot well with them but I would say that is the min. I am shooting 10 off the lands and the boattail jucture is just barely above the neck/shoulder juncture. A .200-.220 would be better.

James

What is your COAL

 

[gsg5pk]

What is the minimum freebore to shoot 215 Berger in .308 win


Do 2013 US FTR chamber was enough? (.343nk, 170fb, 1-30)

Laurie has a long post in here somewhere about seating depths for the 185/200/215 bergers.

Take this for what it's worth, free intenet advice. Don't bother with the 215s in a rifle throated for the 185s.

My base to ogive touching the lands with a 185 Jugg shooting in a 2013 FTR with a .168 FB is ~2.335 with a Hornady tool.

My base to ogive in one of my barrels that i have throated at what consider barely adequate for the 215s is 2.420, that barrel also works with the 200s. If I was thorating solely for the 215s it would probably be closer to 2.50 as the bearing surface is just above the junction in that chamber. I can't check the measurement for the 185s in that barrel, they fall out of the case.

In addition you are going to be taking a big chunk of case space with the tail of the bullet.

I know, you've run the numbers on JBM and if you can get them fast enough they will shoot inside of the 185s or the 200s, so armed with this information you can buy 100 and see. Good luck, but my personal opinion is that if it's not set up for it it is a waste of time. You will be better off shooting the 185s. This does not even get into the recoil management issues most folks (myself included) have with the 215s.

My future rifle which on working at Whidden will be chamber with 2013 US FTR.


Just checking what proper projectile will fit this chamber.


As you state that your load with 185 was BTO 2.335, what is the coal?

 

[XTR]

I had to go measure some bullets, I never measured other than to the ogive.


my loaded 185s are right at 2.990 give or take depending on the Berger lot and jump. I do not shoot 200s in my 185 barrel.



My loaded 200s are about 3.150 and the 215s are at 3.190, and I think that this barrel is a little short in the throat for the 215s.

There are exceptions to every rule, and based on the data on the internet I've got the slowest 30"+ barrels ever made by Kreiger/Bartline because there are lots of guys getting the same or better velocities that I do with 20" barrels.

As a general rule:

you can set up for the 185s and shoot the 200s seated a little deep
you can probably find a freebore that is pretty close to ideal for the 200s and maybe the 185s will still be in the case (not certain of that) and be able to shoot the 215s seated deep
you can set up to shoot the 200s seated long and shoot the 215s seated a little deeper than ideal
you can set up to shoot the 215s and shoot the 230s seated deep
you can set up to shoot the 230s and that's all you can shoot.

If you are getting a .170FB then you want to shoot the 185 Jugg, that's what that reamer was designed for. If it is the 2013 USFTR reamer, the team used 185s.

 

[gsg5pk]

Many thanks for your kindly info.


What is the expected mv for 185 out of 32" Bartlein Barrel?

 

[XTR]

Many thanks for your kindly info.


What is the expected mv for 185 out of 32" Bartlein Barrel?

Expectations and reality are sometimes not the same.

There are a lot of "it depends"

How long do you want your brass to last?
For the most of us who are reasonably sane, something north of 2700 and less than 2800. I recently discovered that a new load I had developed was running a bit warmer than that, and I immediately retested and got it down into another node. I had two firings on the brass, and none of the pockets gave out after two firings, but I didn't want it gone at four either.

I've experimented with a lot of bullets/brass/powder combinations in the last two yrs. I've inadvertently destroyed primer pockets in one shot (as in new primer falls out on desk). Throwing away a box of once fired Lapua Palma brass because you ruined it is painful to me. Throwing another box in the bucket shortly afterwards because it only lasted 4 shots didn't make it feel any better.


I shoot 32s right now too, but I'm not convinced that it helps when shooting the 185s with Varget or Varget speed powder. It may buy you 40FPS over a 30, or it may not. The capacity of a 308 just isn't enough to keep accelerating the bullet in a barrel that long. Two yrs ago after shooting a match with a new 34" I tested it side by side with 30" barrel with a few hundred rounds on it. Identical loads, same reamer and the 30" was 35FPS faster than the 34". I immediately had my smith whack 2" off of the 34. Never have re-done the test, I changed the throat in the 30 before I got it back.

 

[Trevor60]

I had to go measure some bullets, I never measured other than to the ogive.


my loaded 185s are right at 2.990 give or take depending on the Berger lot and jump. I do not shoot 200s in my 185 barrel.



My loaded 200s are about 3.150 and the 215s are at 3.190, and I think that this barrel is a little short in the throat for the 215s.

There are exceptions to every rule, and based on the data on the internet I've got the slowest 30"+ barrels ever made by Kreiger/Bartline because there are lots of guys getting the same or better velocities that I do with 20" barrels.

As a general rule:

you can set up for the 185s and shoot the 200s seated a little deep
you can probably find a freebore that is pretty close to ideal for the 200s and maybe the 185s will still be in the case (not certain of that) and be able to shoot the 215s seated deep
you can set up to shoot the 200s seated long and shoot the 215s seated a little deeper than ideal
you can set up to shoot the 215s and shoot the 230s seated deep
you can set up to shoot the 230s and that's all you can shoot.

If you are getting a .170FB then you want to shoot the 185 Jugg, that's what that reamer was designed for. If it is the 2013 USFTR reamer, the team used 185s.

It is funny as i shoot the 185 and 200's in the same barrel but our OAL are not close to each other.

i use a Davidson seating depth checker which is different then the ones discussed so i will only talk about OAL

185 - 3.030
200 - 3.10
215 - 3.160 "anticipated", i bought the reamer and specked out the freebore and overall length based on the Quickload software and comparing it to my 200's OAL and cutting a 308 case to estimate where the pressure ring is in relation to the neck shoulder junction.
bullet length
185 - 1.345
200 - 1.49
215 - 1.60
The boat tail being past the next shoulder junction is not my primary concern, i want to ensure that the bullets pressure ring (start of the Bearing surface..from the boat tail end) has not gone past the neck shoulder junction.
I jam the 200's and will jam the 215's the 185 was a team bullet so jump (read extracting the round without leaving the bullet behind and getting a powder dump) was a requirement... the 185 jump was excessive, however the groups were tight.

As for speed it depends. 2800+ is reachable with certain actions. i would suggest that you locate an accuracy node and not worry too much about the speed; however on the low end you should be 2600+ to take advantage of what the 185 has too offer.

I use 32" barrels for F/TR

best of luck
Trevor

P.S.

If you are planning to get a reamer the US FTR reamer is fine. you can always ask your smith to throat it out further, that way you are not committed to a reamer that only allows 215s or 230's

 

[XTR]

OALs are difficult because there are a lot of variables.

I've got two lots of 185Juggs right now, one measures lot is 1.371 base to meplat, and the other measures 1.345, my chambers are set up at SAAMI minimum headspace, Jumping or jamming can make a difference of .015 or more depending on the setup, and it's all additive, so two guys with the same reamer spec., shooting the same bullet could end up with a completely different OAL depending on how they tune things.

I will say that the 3.030 looks pretty long compared to my 185s. I jump them, but I've got the 2013FTR not the 2013USFTR reamer. Mine is a .168 FB and I haven't looked but it's always possible that they changed the angle of the lead to allow seating more than the .002 longer that it would appear to have..

 

[Trevor60]

i do not have the USFTR 2013 reamer but when looking at my lengths with the cut away case, it is good and i have sufficient bullet in the case for good tension and release.
My reamer is Vince Bottomley's print #13407 for reference (throated).... it is a Min chamber size. if i were to do it over again i would pick a reamer with a larger back end .4710 and not .4700.

the longer the OAL the further out the bullet; further out the bullet the less pressure; less pressure means you can run faster with more powder before you hit the same pressure levels.

 

[gsg5pk]

Here is the drawing of 2013 US FTR