I wanna make my m305 a true 308 shooter

chemo

chemo

CGN Ultra frequent flyer
Rating - 100%
157   0   0
I know it's explained in the FAQs but sometimes I'm a complete newbie when it comes to understanding english:confused:
I'm planning to start reloading in late spring and most likely going to reload 308 brass as 7.62 is getting rarer every time the sun goes down.
So what I'm really confused about is getting the proper headspace.

1. for 308 we're looking for 1.630 according to SAAMI specs right?
2. what is this:
Dab a little of the valve grinding compound on the rear of the lugs that bear against the receiver locking cutouts
Click to expand...
3.
NOTE: The bolt MUST be stripped in order to properly lag the lugs!!!!
Click to expand...
stripped as in... dissasembled? (lag a lug I don't know what that means...)

in fact theres a bit too much I don't understand... Maybe you're going to tell me if I can't understand this, I shouldn't be doing it, alright fair enough. If you prefer PM'ing me that's fine also. Otherwise, anxious to hear everyone


Carlos
 
Lap the lugs. The stripped bolt is assembled into the receiver, and the bolt lugs are worked against the locking shoulders in the receiver so that the surfaces make full contact. The abrasive paste laps the lugs and shoulders.
This will also tend to increase the headspace. Don't do it unless headspace insufficient. It would be very unusual for a M305 to be tight for .308 as received.
Use headspace gauges to find out what the situation is with respect to your rifle. Contact Hungry, send him some fired cases, he will measure them for you.
 
first off send 3 casings to hungry and get him to measure the headspace for you- BEFORE YOU DO ANYTHING ELSE-you MAY NOT NEED TO DO ANYTHING
lapping a bolt is a job for a smith,and one experienced with m14 actions at that- you start changing angles with lapping compound and yhou may up needing at least a new bolt and maybe a whole new rifle as one fits the other
my old norc seen only commercial 308 loads or my handloads for almost 20 years ( and it is one of the ones with the supposedly excessive headspace_) and never had a problem- it's according to the rifle itself,each one being different
 
but from my understanding, most of newer 305 have headspace a bit bigger than that of the 308 saami spec, which turns out to be alright so far? the only problem would be with too little headspace, right?
 
Last edited:
charles.emond said:
but from my understanding, most of newer 305 and headspace a bit bigger than that of the 308 saami spec, which turns out to be alright so far? the only problem would be with too little headspace, right?
Click to expand...

Yeah, unless you have a USGI bolt, lapping shouldn't be needed as the headspace is already over the saami no-go. You may know your headspace by measuring the fired cases, hungry does it with a RCBS precision mic. If you have a friend who has this tool ask him to measure them for you or you can mail a few fired cases to hungry and he'll tell you if your #### is going to fall off :runaway:
 
yeah i know someone who can do it for me just around, but i have yet to fire it :D i need to join an outdoor range and quite frankly i'm not sure my sadlak aluminum mount will stand the cold
 
most norcs of the 2007 stamped variety have been headspaceing at about 6 to 9 thou over the 7.62 GO guage. In other words headspace measurements of 1.641 to 1.644 . Getting past 1.644 and still trying to shoot .308 commercial..... I don't advise it. I have had neck seperations in commercial brass even with a chamber that guaged 1.640.

For the average norc, feeding it both .308 and 7.62 is generally acceptable.... but it would be wise to verify the headspace if you are concerned. As the guys have stated above, there are folks here willing to Mic your brass to tell you the chamber dimension you have.

I took my latest build to the extreme and installed a Krieger stainless barrel and a TRW usgi bolt. First the bolt needed to be "lapped" in to the receiver and then I had to cut the chamber to final length and I chose 1.631, one thou over 308 Go. She shoots .308 like a hot damn but surplus 7.62 x 51 is now OFF LIMITS for this rifle.

You will not achieve .308 chamber dimensions without change parts, noteably the bolt. A properly lapped in Usgi bolt is the answer, everything else on the rifle stays.
 
charles.emond said:
i'm not sure my sadlak aluminum mount will stand the cold
Click to expand...

I have one on my shorty and it survived cold... Why would it fail ? Unless you wack the rifle (scope & mount first) on a rock it will keep going. Just make sure the bolt are tight as sadlak says all will be fine :sniper:

For its price and weight this mount is great.
 
does anybody with an m305 have the receiver stamped 7.62 NATO or 7.62X 51? mine is stamped .308.. oddly enough it doesn't say 308 WIN.. based on this i figure 308 win is the prefered cartridge for the m-305. (even though you can shoot 762 NATO with it)
 
i believe the .308 designation was just the chinese way of labelling the m14s/m305 as a sporting/hunting rifle. If it was labelled 7.62x51(Nato) as it should be, it would fit the bill as an assault weapon ;) Even now, the us. is banning export of items with military chamberings...... but .308 is a "hunting/sporting" caliber so those items are handled differently.
just my take on these things
 
charles.emond said:
I know it's explained in the FAQs but sometimes I'm a complete newbie when it comes to understanding english:confused:
I'm planning to start reloading in late spring and most likely going to reload 308 brass as 7.62 is getting rarer every time the sun goes down.
So what I'm really confused about is getting the proper headspace.

1. for 308 we're looking for 1.630 according to SAAMI specs right?
2. what is this:

3. stripped as in... dissasembled? (lag a lug I don't know what that means...)

in fact theres a bit too much I don't understand... Maybe you're going to tell me if I can't understand this, I shouldn't be doing it, alright fair enough. If you prefer PM'ing me that's fine also. Otherwise, anxious to hear everyone


Carlos
Click to expand...

Don’t waste your time just neck size you brass after they have been fired in you rifle the they will be the size of you chamber make them with a colored marker so that they don’t get mixed up with other brass you will be amazed at how you groups will tighten up with out any mods to the gun. Ask Hungry if you don’t believe me you #### will not fall off.
 
valmet762 said:
does anybody with an m305 have the receiver stamped 7.62 NATO or 7.62X 51? mine is stamped .308.. oddly enough it doesn't say 308 WIN.. based on this i figure 308 win is the prefered cartridge for the m-305. (even though you can shoot 762 NATO with it)
Click to expand...

Mine says 308win the cartridge is the same size it is just the pressure is less in the 7.62
 
klrklr said:
Don’t waste your time just neck size you brass after they have been fired in you rifle the they will be the size of you chamber make them with a colored marker so that they don’t get mixed up with other brass you will be amazed at how you groups will tighten up with out any mods to the gun. Ask Hungry if you don’t believe me you #### will not fall off.
Click to expand...

so if i get your point, painting my brass will give me tighter groups? LOL
 
You must log in or register to reply here.
Back
Top Bottom