2.23 vs 5.56

[oneyeopn]

But to get accuracy for that distance with the heavy GR bullet, u also need a 1/7 twist barrel. Which we all know handles heavier GR bullets much better than the normal 1/11 1/9 barrels.

So in reality i guess it depends on what the OP is trying to achieve. But for what it sounds like IMO, he just wants something to plink around with. That 75gr bullet will cost him more than the average 45-55gr plinking bullets. So unless he has something that handles the 75gr bullets (well), then I see no reason for him to need them. IMO, your typical AR with a 1/9 twist barrel chambered in 5.56 or multi should work just fine.

The "T" has a 1:8 5R barrel and will shoot the 75gr as well as the 1:7. The problem I have found with the 75gr is a 16" barrel is just not long enough to really stabilize the bullet and also Hornady right on the box says 1:7 to 1:10. The only real difference becomes the bullets RPM's and there just isnt that great a difference.

 

[Smitty357]

Just to clarify and make sure that I have this correct. My M&P15T is marked 5.56. The good ol manual that came with it states to use nothing but what is stamped on the barrel. The exception to that is I can use both the 5.56, and the .223 without any sort of problems, or worrying about any failures? I know its a noobish question, and yes I am still very new to this world of black rifles. Thank you for the clarification.

Shane

U are correct, u are good to go with either 5.56 or .223.

 

[Cidian]

Thank you Smitty, I just wanted to make sure and not blow myself up. Lol


Shane

 

[zip777]

http://en.m.wikipedia.org/wiki/5.56x45mm_NATO

Read this Wiki. Very informational. I'm sure you already know in a populated area you understand it's the bullet choice which is more important than chamber pressure. A SP or BTHP round should be used vs FMJ which can shoot right through your house into your neighbors house. You want a round that hits and expands. You didn't mention this as a proposed use for your firearm but I thought I'd mention it just in case.

 

[riderrick65]

Hell I'll take anything I can find right now! Local Walmarts don't have squat and I have spent hours on the internet looking for whatever! I guess I'll just have to place some on back order and in the mean time try to find some locally ...... I am really beginning to think that this was a bad idea trying to get into the AR platform at this stage of the game. Everything that I wanted to purchase is on back order and who knows whats going to happen with this gun-ban legislation.

 

[zip777]

http://www.doubletapammo.com/php/catalog/product_info.php?cPath=21_56&products_id=296

Buy it.

 

[zip777]

http://www.cabelas.com/product/Shoo..._f39e692f&WT.mc_id=al56335&rid=12&WT.tsrc=AFF

Option 2.

 

[zip777]

Update skip the cabelas link. It's an LCT bullet. Go with the doubletap.

 

[zip777]

I looked again on the Cabelas link the 55gr FMJ is backorderable at $10 for 20.

Hope this helps ya man!

 

[Maddmax]

I've got a lot of IVI SS109 which I suppose was rejected for pressure that will pop 3-4 crimped primers in every mag and this in two Colt uppers I tried it in, a 20" and a 16". You get one in the bolt recess and you have the mother of all jams. I figure that someday I will pull it down back the powder charge down a few tenths and reload but have been too lazy so far.

I check the primer pocket sizes. They sound too big.