 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Farmer47 is correct. I have a LMT CQB Ar15. The barrel is stamped 223. I contacted LMT and they said some of their barrels had to be stamped 223 instead of 556 so they could be exported to Canada. LMT assured me I could use 223 or 556 in their rifles. If in doubt check with the manufacturer.Originally Posted by farmer47
I'd send a e-mail to Ruger with the serial # to make sure!In efect the rifle that I am looking at is a Ruger mini 14 target model. Ruger expressly states 223 only for this model,but the ranch model will except ether 223 or 5.56.
I ran 5.56 in a 223 stamped gun. Asked around everyone said it would be okay don't worry gun shop told me it was there idea.Went to clean my gun after 150rounds and found the bolt cracked and fragmented. Not gonna do that again but I do wish my gun was stamped 5.56.if it's not stamped don't do it.
Speaking of the MR1, you read my mind I was just going to bring it up.... I bought one last summer and absolutely love it! I am reading online that it can shoot 5.56 as well but I am afraid to chance it as the barrel is marked .223 and it cost me a fair bit. Does anyone know for sure if the MR1 was chambered for both because the local store has a good deal on crates of 5.56 that are tempting me.I'm a big fan of the Benelli MR1 model without a pistol grip. It does everything better than a Mini 14 (except price, but better costs money).
my DDM4V5 is stamped .223 but can fire 5.56.
I would invest some time in researching the target model vs the standard one(if you haven't already). It seems like the biggest difference is weight. I could be wrong!
SAAMI, and North Americans in general, are the only ones who particularly differentiate between the two.
The rest of the world considers the differences to be within normal manufacturing variances and tolerances. In countries that legislate against arms capable of firing military cartridges, they specifically link the two cartridges.
Historically, the difference was for marketing purposes. .223 Remington was marketed to the civilian population as a varminting/ranch cartridge, but they wanted to avoid the association as a small game round when used as a military cartridge (the origin of calling the M16 a "Poodle Shooter" stems from the civvy variant of the cartridge being used to hunt prairie dogs and coyotes).
Same thing with the HK MR223. Actually chambered for 556.
The bigger issue for 308/762 is headspacing.
.308/7.62 is the opposite of .223/5.56. Commercial 308 hunting ammo will be hotter than 7.62x51 Nato ammo. 308 is 60,000psi while 7.62 Nato is 50,000psi, although they measure the pressure differently (copper crush washer vs pressure transducer). The head space is also different between the two along with internal case capacity (7.62 has thicker brass meaning less internal volume). 7.62 Nato can be safely fired from any 308 chamber. If using 308 in a 7.62 Nato gun, make sure you check the headspace first. Further, the pressure curve for 308 may not agree with the gas system on some semi Autos like the M1, this can cause anything from accelerated wear of the moving parts to failure to cycle properly or even catastrophic failure of the firearm in extreme cases. The Norc M305 copies "should" be able to digest either or, but still check your headspace if you plan on using 308 hunting ammo regularly.
Stand by for CGN corrections
If you want to make absolutely sure you are safe to run 762 in a 308, check the following:
The bolt should close correctly on a 7.62mm Go Gauge of 1.6355", should not close on a 7.62 No Go Gauge of 1.6375" or the .308 Field Reject Gauge of 1.638".
The issue is that a rifle could be in spec using 308 gauges, or 7.62 gauges, but be out of spec for the other cartridge.
308 Gauges:
- 1.630" GO
- 1.634" NO GO
- 1.638" FIELD REJECT
7.62 Gauges:
- 1.6355" GO
- 1.6375" NO GO
- 1.6455" FIELD REJECT
Posting Permissions
