Federal Gold Medal Match SMK 168 grain...could it possibly be .230 off the lands?

[boisepaw]

I know every rifle is different.

I'm working on a load for my 308 rifle and have used the Hornady Comparator to measure the length to the ogive of the 168 grain SMK bullet when touching the lands. I came up with a length of 2.440

Then just for a point of reference I measured a factory FGMM SMK 168 round and came up with a length of 2.210. So it looks to me as though the factory round...in my rifle...is .230 off the lands. Is it possible that they load the factory round that short?

 

[boisepaw]

The rifle is a factory Remington 700...

 

[EN2722]

A few questions for you.

Is the measurement of 2.210 from the ogive or overall length?

Which model 700? Stock barrel?

How many times did you use the Hornady comparator? Did you did it once or more and then get the average?

 

[boisepaw]

All measurements are to the ogive.

Model 700 Varminter. Stock barrel.

I measured it five or six times and took the average.

 

[EN2722]

That’s from the Lyman 50th Edition. It shows the OAL of 168 gr BTHP at 2.775 vice the 2.80 that is the book OAL.

I would measure OAL and see if it compares to the 2.775 OAL. I’d do it but I currently do not have any 168’s on the shelf. Just 175/178.

Normally, in my experience factory ammo is very, very close to book data.

 

[boisepaw]

That's helpful information and I understand what you are saying. I'm just trying to figure out if it is possible that factory ammo is loaded THAT far off the lands. I've just never checked it before but I figured that since conventional wisdom (for many folks) is that the shorter the jump to the lands the better...that seems like a REALLY long jump.

 

[Steel head]

That's helpful information and I understand what you are saying. I'm just trying to figure out if it is possible that factory ammo is loaded THAT far off the lands. I've just never checked it before but I figured that since conventional wisdom (for many folks) is that the shorter the jump to the lands the better...that seems like a REALLY long jump.

I think it could totally be real.

 

[918v]

I would use a different tool. Hornady tools tend to give wild results when used by noobs. 2.925” COAL is pretty common with SMK.

 

[boisepaw]

I would use a different tool. Hornady tools tend to give wild results when used by noobs. 2.925” COAL is pretty common with SMK.

Ummm...I won't take offense but I've been using the comparator for four or five years.

I've just never measured a factory round in the process of developing a new load so I've never taken the opportunity to see how factory ammo compared to reloads with regard to distance off the lands. Thus my question...

 

[EN2722]

That's helpful information and I understand what you are saying. I'm just trying to figure out if it is possible that factory ammo is loaded THAT far off the lands. I've just never checked it before but I figured that since conventional wisdom (for many folks) is that the shorter the jump to the lands the better...that seems like a REALLY long jump.

I absolutely believe it. Factory ammo is loaded to be safe IMHO. They do not make it specifically to be 2 thousands off from the lands because there’s a lot of barrel manufacturers with different reamers. So, they follow the book data.

Hence why it’s recommended to buy a few boxes of different ammo and see which your gun likes.

I haven’t purchased ammo in a better part of a decade so I’m not familiar with the current offerings. However, if my memory serves me correct the last box of factory Ammo was Hornady 130 gr SST for my 270 Win...I’ve since developed a load that shoots significantly better with 140 gr TGK from Sierra.

 

[Bradv86]

My factory 700 .308 barrel has a long jump to the lands. Using 155 SMK I am jumping .140 seated at 2.86 OAL (mag restriction). It would obviously be even further, about .200, if loaded to an OAL around 2.80 which would be typical for factory ammo to fit in standard boxes of your off the shelf rifle.

I would wager that even if you are a small amount off in you measurements that you are jumping a long ways.

 

[pmclaine]

FGMM is buried into the brass.

Lots of free bore.

Still shoots like a fine Rye in every .308 out there, especially the 168.

 

[FLIGHT762]

Factory ammunition is loaded to a COL where it will fit into a magazine. For 308 Winchester it will be not over the SAAMI maximum of 2.800". I suggest you measure some factory 168 FGMM to see what you get. You should get measurements around 2.800".

Remington factory throats are very generous. That is what they are.

I just measured a factory box of 168 FGMM. The COL measurements were 2.795"-2.800"

So yes, the factory 168 FGMM will be a good distance from your factory lands. If you want to be closer to the lands with a magazine fit, you will need a new barrel cut with a reamer that has a shorter throat.

I have a 24" Hart barrel that was reamed with a reamer that when brand new, I had to take Factory 168 FGGM ammo and seat the bullets in about .020" to avoid jamming them into the lands until the lands smoothed out after a couple hundred rounds.

Even with the long jump in your rifle, 168 FGMM usually shoots very well.

Your rifle is normal.

 

[918v]

Ummm...I won't take offense but I've been using the comparator for four or five years.

I've just never measured a factory round in the process of developing a new load so I've never taken the opportunity to see how factory ammo compared to reloads with regard to distance off the lands. Thus my question...

So? There are reloaders claiming 50 years of experience who don’t know what they’re doing. Many people run into problems using Hornady comparators.

If you wore out your barrel then you might have .230” of jump, but normally Remington cuts their 308 chambers much shorter than that.

 

[Doom]

The rifle is a factory Remington 700...

That’s the answer. The Rem 700 has a long leade. Forget chasing the lands. My rifle when new had only the SMK boat tail in the case mouth when touching the lands.

 

[pmclaine]

Twenty 175 FGMM base to ogive....

Base to ogive 168 FGMM 10 rounds.....

Something tells me Fed thinks 2.23 is a good jump.

 

[918v]

BTO on SMK varies a great deal from lot to lot. But Federal loads FGMM to 2.8” consistently. I once had 2 lots of 175SMK that were .060” apart.

 

[gunsnjeeps]

FGMM is like M118 LR its a mag length load. My first try at 1K I tried to load to the lands and couldn't find them. SMK's are generally jump tolerant.

 

[Lunchbox27]

How has the FGMM been shooting in your rifle? If its good, load to the same length.

I have quite a few 308 barrels. Some factory, some custom. All shot really well at 2.810 oal.

 

[NCHillbilly]

Factory ammunition is loaded to a COL where it will fit into a magazine. For 308 Winchester it will be not over the SAAMI maximum of 2.800". I suggest you measure some factory 168 FGMM to see what you get. You should get measurements around 2.800".

Remington factory throats are very generous. That is what they are.

I just measured a factory box of 168 FGMM. The COL measurements were 2.795"-2.800"

So yes, the factory 168 FGMM will be a good distance from your factory lands. If you want to be closer to the lands with a magazine fit, you will need a new barrel cut with a reamer that has a shorter throat.

I have a 24" Hart barrel that was reamed with a reamer that when brand new, I had to take Factory 168 FGGM ammo and seat the bullets in about .020" to avoid jamming them into the lands until the lands smoothed out after a couple hundred rounds.

Even with the long jump in your rifle, 168 FGMM usually shoots very well.

Your rifle is normal.

Another example: I recently loaded some 300WM ammo that the load manual said to load 3.340". Loading my rounds to the lands gave me an overall length of 3.600". Factory ammo will always be at or below sammi specs, which may be nowhere near YOUR your optimum oal.

 

[flyright]

If FGMM was loaded to "fit" the longest Remmy factory throats, none would fit the mag and they'd be really jamming a lot of other factory barrels. But, at spec, they still normally shoot well even with all the jump.

 

[boisepaw]

If FGMM was loaded to "fit" the longest Remmy factory throats, none would fit the mag and they'd be really jamming a lot of other factory barrels. But, at spec, they still normally shoot well even with all the jump.

I don't know why I never figured that out before. I had just never measured factory ammo. When I started reloading all I heard about was how important it was to get close to the lands. And I knew that factory ammo wouldn't attempt to do that. But learning about reloading I was hearing experts say that it was odd and innovative to go .130 or more off the lands. So it caught me by surprise that the factory load would be almost twice that far off the lands.

I'm still learning...

 

[Powder_Burns]

Haven’t really studied the 168smk profile yet, majority of my .30 cal workup was with berger vld’s...
but if the smk has a tangent ogive it is going to be less sensitive to bullet jump to the throat. Chasing the lands is more critical shooting long pointy bullets with secant ogives.

I would think since the 168 smk gives good results in so many different guns it would have more of a tangent ogive and thus not sensitive to your seating depth in regards to freebore.
Load to factory OAL and forget about it.

 

[NCHillbilly]

I don't know why I never figured that out before. I had just never measured factory ammo. When I started reloading all I heard about was how important it was to get close to the lands. And I knew that factory ammo wouldn't attempt to do that. But learning about reloading I was hearing experts say that it was odd and innovative to go .130 or more off the lands. So it caught me by surprise that the factory load would be almost twice that far off the lands.

I'm still learning...

I don't know why I never figured that out before. I had just never measured factory ammo. When I started reloading all I heard about was how important it was to get close to the lands. And I knew that factory ammo wouldn't attempt to do that. But learning about reloading I was hearing experts say that it was odd and innovative to go .130 or more off the lands. So it caught me by surprise that the factory load would be almost twice that far off the lands.

I'm still learning...

Never hurts to ask. I've been loading for 25 years and I still learn stuff on here almost daily. Plenty of folks on here are happy to help.