Long throats?


Well-Known Member
Jan 16, 2007
North Idaho
What is the deal with the ultra long throats with manufactures lately? I just picked up another sendero sf2 and the throat is rediculously long. There is absolutely no way I will get a bullet less than .040" off the lands? I know how to fix the problem but just don't get why. The caliber is 7rum. My sendero sf2 in 7rm is perfect. I am going to try bergers off the lands for the first time although I haven't had good experience with this in the past.
I would assume it has to do with more freebore, less pressures, ie safety factor on the manufactures part in reguards to liability issues. But I have not heard of this issue until now. I would be interested to see if others post similar issues.
I purposely had a long throat cut in my 300WSM so I could fit the longer bullets out farther for better case capacity. It didn't come out quite like I wanted too, but I finally found a powder a load that is acceptable. I'm guessing manufacturer's are getting on board with guys loading ultra long bullets and giving you that ability without gunsmithing. I would imagine it is going to be common practice in 7mm, 30, and 338's.

I think it definately has to do with both keeping pressures at safe levels for the average Joe, and for using longer bullets. My 5-R has a .135 jump when loaded to the maximum length of the mag. I was quite a bit concerned when I first measured it but relieved when it shot so well.
In order to impress the shooting public , More velocity was nessary .And with more
velocity comes more pressure . So they went with more free-bore to safely get the velocity
and sell the "New Calibers".

Roy Weatherby did this many years ago and sold a lot of rifles.

Free-bore is not the enemy. Poor chambers,Barrels,head-space and stock fit contribute more to
inaccuracy than any thing else.

There are a lot more rifles being built with free-bore that most know about (And the rifle
manufactures are not going to tell so only the re loader is going to know.

If they built quality rifles it would not be a problem and that's why most won't give an
accuracy guarantee.

The best example that I know of would be to chamber a 30/378 with a short throat (Little or
no free bore) and try to shoot factory 30/378 ammo in it . Most of the time it will blow the
primer (Not good) in perfectly safe ammo if fired in a SAAMI 30/378 chamber with "Lots of
free bore".

I noticed this in my 700 SPS-V a while back also. I can't load the bullets out far enough to touch the lands. I can't tell however that this seems to have a significant impact on accuracy. I am shooting 168 smk and they seem to make the jump fairly well.
I agree that manufacturers were probably trying to get pressures down. Unless a person handloads,however; they have defeated the purpose of the high velocity that sells the cartridge in the first place. The upside of course is that even higher velocity can be achieved for the handloader by loading back up to original pressure. This is of course due to increasing volume before the bullet engages the lands. I once read an article written by "an expert" that stated the 6.5-06 A.I. actually produced LESS velocity than a standard 6.5-06. He was loading the two with the identical load. DUH! Same principal, he had more volume which created less pressure and of course lower velocity. Hopefully someone will start designing magazines that correspond with throating. A lot of us end up shooting our bolts as single shots:D:D...Rich
I called Rem about a 7mm SAUM expressing concern about not being able to get loads out to the lands because of the short magazines and was told it was designed that way for safety.......... I guess their lawyers are designing thier guns now...... wish it didn't cost so much to get custom rifles built..... but the gun smith has to make living as well.
This is one of the reasons I like Savage rifles. Buy a premium barrel for three or 400 bucks, do the work myself, end up with a great shooter for a fraction of the cost of a custom rifle. I have a .308 that will shoot 5/8" groups with 47grs 4064 and 150gr SGK's. ALL day! I might have 700 bucks in it.
J E Custom is correct properly cut chambers and throat diameter dimensions are more important to accuracy than throat lenght.

I've owned some rifles that I could not get close to the throats yet they shot very accurately none the less
Warning! This thread is more than 14 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.