tag:blogger.com,1999:blog-1592992209402300549.post2601651316440837934..comments2024-03-28T08:06:43.198-04:00Comments on The Silicon Graybeard: A Little More About .308 vs 7.62x51SiGraybeardhttp://www.blogger.com/profile/00280583031339062059noreply@blogger.comBlogger19125tag:blogger.com,1999:blog-1592992209402300549.post-58177944999401589532021-08-21T10:40:07.765-04:002021-08-21T10:40:07.765-04:00Please note that this is a comment to a seven year...Please note that this is a comment to a seven year old post, so that's why your comments didn't show up originally. I moderate comments to older posts and get them mailed to me so that I can know the comments come in. <br /><br />As for your question, you don't say if .308 Win cases split but 7.62x51 don't or if 7.62x51 cases split but .308 Win don't or if everything splits. <br /><br />I'm going to go with the guess that the .308 cases split and Milspec don't, because (as the post says) the Milspec cases are built with a thicker wall. Which is saying the barrel is marked right and the lower is wrong. I've never had that situation, but I think going with what the barrel says is the way to go. <br /><br />The quoted references in the article say the two cases have the same external dimensions and the 7.62 has a thicker wall which is why I'm thinking they're not breaking. It might be the chamber is oversized a bit. <br /><br />It's probably a question for whoever made the rifle but I hope it's helpful. <br /><br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-86095755759319244442021-08-21T03:26:10.631-04:002021-08-21T03:26:10.631-04:00I can not figure out why, I take very good care of...I can not figure out why, I take very good care of all my firearms.Anonymoushttps://www.blogger.com/profile/11708818838938924541noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-87772824448138906282021-08-21T03:25:11.677-04:002021-08-21T03:25:11.677-04:00Ok so why does my lower say .308, and my barrel sa...Ok so why does my lower say .308, and my barrel say 7.62x51? My cases are splitting right down the neck on all of them..unless I shoot steel case.Anonymoushttps://www.blogger.com/profile/11708818838938924541noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-65606741893422142017-12-16T06:38:51.405-05:002017-12-16T06:38:51.405-05:00I load 2 gr under max in both cases, 308 and na...I load 2 gr under max in both cases, 308 and nato. fired from the same rifle, and in every type of powder and bullet, Never had a problem, EVER then bump up to just under max, still no problem., Nato, VS 308, they all shoot the same and do the job . Just size the brass, and trim it , then load and shoot , 25 years of doing this, well it tell me something Jimmyhttps://www.blogger.com/profile/10342980610238690442noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-36251049998419346072016-10-09T20:18:20.174-04:002016-10-09T20:18:20.174-04:00He had it backwards He had it backwards KN6RELhttps://www.blogger.com/profile/07722249870946609145noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-22653724080997913752016-09-05T23:55:23.933-04:002016-09-05T23:55:23.933-04:00AS of today, 9/5/16...Springfield's web site s...AS of today, 9/5/16...Springfield's web site says M1A can use 308 ammo. I'm pretty sure when they were building M1A'a with surplus M14 receivers and chambers they recommended 7.62x51, but not any more. I've shot both in my M1A with zero problems for the past year.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-67098491659278158452016-04-15T09:07:34.307-04:002016-04-15T09:07:34.307-04:00Thanks for coming by with that. Considering how r...Thanks for coming by with that. Considering how recently "buckandbev" posted about their rifle wanting only NATO 7.62, it seems to mark a change for the SA folks. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-88325075264639562632016-04-15T03:23:23.484-04:002016-04-15T03:23:23.484-04:00Having recently bought my second M1A, I called Spr...Having recently bought my second M1A, I called Springfield Armory to check on this (about a month ago). I was told specifically that they could use either .308 or 7.62x51. I repeated the question to verify, and was again told that I could use .308. There was nothing in the literature accompanying the rifle to indicate otherwise, but I was just checking to be sure.OldCorpsEdhttps://www.blogger.com/profile/03965060796565622421noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-68215738085145643792016-03-02T01:47:21.482-05:002016-03-02T01:47:21.482-05:00Springfield armory states strongly that only 7.62 ...Springfield armory states strongly that only 7.62 be used in the M1A. That according to the information sent with the rifle. They worn of thin primers used in the 308 rds that could result in "slam fires" caused by the firing pin strike at the load/locking stage of the cycle..<br /><br />Use the M14 years ago but used military ammo. Any one have any bad moments using over the counter 308 in any of the M1 based rifles.buckandbevhttps://www.blogger.com/profile/07388324926374808655noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-68751435770104597042016-02-28T19:05:39.985-05:002016-02-28T19:05:39.985-05:00It's always safest to use whatever the barrel ...It's always safest to use whatever the barrel says it is, but by all means, check with DPMS. The barrels are supposed to be marked when the chamber is formed, and be the correct caliber. <br /><br />I'd use the NATO ammo with it, but again, I'm just "some dood on the internets" <br />SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-70474644178583384382016-02-28T18:53:14.614-05:002016-02-28T18:53:14.614-05:00I have a DPMS 308 Oracle, LR308. The lower receiv...I have a DPMS 308 Oracle, LR308. The lower receiver indicates Cal. 308, but the underside of the barrel is marked DPMS 7.62x51 1-10. What is the proper cartridge to use? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-56685921959183226112016-02-09T09:32:06.609-05:002016-02-09T09:32:06.609-05:00I feel really uncomfortable with answering this be...I feel really uncomfortable with answering this because I have no idea what you have. What does the head stamp on the brass say? <br /><br />What I get as the takeaway from this is that with a rifle marked ".308 Win", you can run NATO or .308 Win commercial and it'll be OK. If it says "7.62x51", you need to stick with that. That's the opposite of .223/5.56 where the NATO chambering will handle both and the .223 Remington chamber is only for that. <br /><br />I have a DPMS marked ".308 Win" and have run both types in it, with no jams or no failures to cycle. (Well, I had one bad lot of Magtech, but they knew about it and replaced it with no questions asked). <br /><br />Disclaimer: I'm just some dude on the Internet with a blog. I really hope this works, but there's no way I know what you've got. SiGraybeardhttps://www.blogger.com/profile/00280583031339062059noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-78380961732212211512016-02-09T01:21:13.254-05:002016-02-09T01:21:13.254-05:00came across some 20/box ammo labeled "308 Win...came across some 20/box ammo labeled "308 Win. 7.62x51" Fed. Lake City . What can this be safely be fired in - no reloading of brass? Never seen ammo labeled as such. I have two AR format rifles, one stamped "308" and the other barrel stamped "7.62 x 51 NATO". Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-12050074772708889782014-08-14T22:04:22.478-04:002014-08-14T22:04:22.478-04:00Holy Shit the ignorance of this author is going to...Holy Shit the ignorance of this author is going to get people hurt. The SAMMI specs list the 308 round as higher pressure than the NATO 7.62.51 round. This is inverese to the 5.56x45 versus the .223 whereas the 5.56x45 is higher pressure. The SAMMI/CIP maximum pressure for the .308 Win cartridge is 62,000 psi, while the 7.62x51 max is 50,000 psi Sheesh.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-79939126280421683402014-08-10T18:26:43.110-04:002014-08-10T18:26:43.110-04:00If the Ishapore won't quite close on a "N...If the Ishapore won't quite close on a "No Go" guage that means the chamber is shorter than max allowed.<br /><br />You also need to know if the bolt WILL close on a "go" guage.<br /><br />If it closes on a "Go" but not on a "No Go" then you are fine.<br /><br />Avoid anything marked "Superformance" or "Light Magnum" though, as they are really meant for modern bolt action rifles only.SordidPandahttps://www.blogger.com/profile/00657526230826604643noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-41776863168003640732014-08-10T13:40:46.251-04:002014-08-10T13:40:46.251-04:00So - the question that has been afflicting all of ...So - the question that has been afflicting all of humanity since the moment of creation: is it OK to shoot .308 in an Ishapore Enfield that won't quite close on a .308 no-go gauge?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-75805887602457418862014-08-09T17:52:49.370-04:002014-08-09T17:52:49.370-04:00So, if you don't reload, they're the same....So, if you don't reload, they're the same.<br /><br />The number one killer of NATO chambered guns is not reloading mistakes but surplus ammo. Ammo which is supposed to be FOR said NATO chambers...<br /><br />The worst I've seen of .308 in NATO guns has been the occasional split case mouth.<br /><br />I also wonder exactly what chamber is on a DSA FAL or a Springfield M1A or a PTR. If present day made guns are .308 then this is all machts nichts.<br /><br />It's been mentioned, if this was a serious problem we'd be seeing no end of rage and froth on every forum there is about broken guns and ruined brass.<br /><br />Of note is SAAMI doesn't list the interchange as one of the unsafe combinations.Angus McThaghttps://www.blogger.com/profile/09295013525738248801noreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-9687358108289858782014-08-09T07:00:06.281-04:002014-08-09T07:00:06.281-04:00You touched on it, but didn't continue express...You touched on it, but didn't continue expressing the thought: Since 7.62X51 brass is thicker, especially at the case head, internal case volume is significantly lower in 7.62X51 brass than .308 Winchester brass. (The reason for this is the violent extraction particular to full auto firearms, especially the 7.62 miniguns, which extract while the firing chamber still contains pressure from firing; a minigun will rip the case heads off .308 brass.) And, by "significantly" I mean "enough to cause a pressure difference."<br /><br />This reduced case volume leads to higher pressures if using the same powder charge in 7.62X51 as one uses in .308 Winchester cases when one reloads. Most reloading manuals mention this (all of my manuals are older, so I don't know what's in the newest editions), but I'm not aware if they stress it.<br /><br />The point being, since greatest accuracy in almost any cartridge is achieved with the case about 95% full of powder (some powders, and WW296, a shotshell powder also used for magnum pistols is one example) come with a caution to load to at least 90% of case capacity in magnum pistol calibers to ensure proper powder powder ignition and burn) some reloaders may jump to the right side of the powder charge table without starting with lower charges and working up. <br /><br />The reloading rule of thumb is start <i>no higher than 85-90%</i> of maximum listed charge and work up gradually, looking for pressure signs (which, SiG, might be a good topic for a future post). And, when working with .308 Win / 7.62X51 rifles, unless charges are well below maximum, it's a really good idea to keep your brass segregated. Not only will that help prevent possible pressure problems, the pressure differential from the same load in the different internally-sized cases will cause a velocity difference which affects accuracy; if you're seeing vertical stringing on the target, mixing 7.62X51 brass with .308 Win and reloading them to the same charge level can be one cause. <br /><br />Aliennoreply@blogger.comtag:blogger.com,1999:blog-1592992209402300549.post-89211184618469516752014-08-09T00:54:33.817-04:002014-08-09T00:54:33.817-04:00Winchester white box .308, 147 gr FMJ, 2800 fps.
...Winchester white box .308, 147 gr FMJ, 2800 fps.<br /><br />US M80 ball, 147gr FMJ, 2750 fps.<br /><br />If NATO is loaded hotter, it sure is wasted on the velocity numbers.Angus McThaghttps://www.blogger.com/profile/09295013525738248801noreply@blogger.com