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I have heard from a couple of different sources that FMJBT rounds tend not to be as accurate in the Mini 14 as regular FMJ rounds. Because of this I have avoided buying them. I've also heard that the heavier grain bullets work better with the 1:9 twist of the barrel. Any truth to this?
 

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Before you shoot 5.56 through a .223 marked barrel, I would recommend considering the following concerns:

Well, in short yeah you can shoot 5.56 through your .223 barrel, but are there issues with doing it, well maybe so... Will it blow your gun aparts and send pieces of the gun thru your brain housine group, probably not. But lets take a look at what the issues are for reals.

First of all there are three major types of AR chambers. The .223 SAMMI, the .223 Wylde and the 5.56 NATO. It's all so crazy and convolutted that we will skip right to the point of it all and look at it in laymans terms.

The real issues are the case neck, freebore length, throat angle and headspace. Now what do they each mean?

Case neck- Thats where the bullet sits in the case.

Freebore length- Thats the length between cases end and where the lands and groove start. This is where the bullet is actually free in the bore when it leaves the case. This affects the pressure of the round as the lands and grooves cause pressure to build behind the bullet.

Throat angle- This is the angle of slope where the freebore ends and transitions into the lands and grooves.

Headspace- This is the depth of the chamber

Now the headspace on all chambers is the same at 1.4636, so that is a non issue. The throat angle is significantly different though, 3 degrees for the SAMMI and 1.25 degrees for the other two. How does this affect you? It makes the pressure in the SAMMI start quicker as pressure is appled more abruptly.

Freebore length is a big issue in the three. The freebore for the SAMMI is a mear .025, the Wylde is .062 and the 5.56 NATO is .057. What does that mean? It means that the SAMMI builds pressure a lot faster than the Wylde or NATO chambers. Add this to the fact that NATO rounds are already a few hundred feet per second faster and as much as 5,000 PSI higher in oressure and you have an issue building rapidly. As is the pressure.

Does this mean that your gun is going to explode by using NATO ammo in your .223, probably not. They are massively over engineered and generally pretty safe for these kinds of things. They are designed to take pressure spikes, however I DO NOT RECOMMEND IT. It simply is not safe. You WILL probably start to see primers popped out of the cases or swollen.

So what do we do about it all? Well, we try to order all of our AR's in the 5.56 chambers. That allows you to shoot whatever you want to in the gun. The next thing you can do is shoot .223 ammo in your guns. Milsurp is not as cheap as it used to be, so there is not much advantage to go that route anymore. But if you do find a deal having a 5.56 chamber is going to make life more comfortable for you. But if you dont have a 5.56 chamber, just don't shoot milsurp ammo.
 

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If your Mini is a 5.56 and it probably is....the gun will tell you what it likes, try some different brands and bullet weights. My AR's are 1/9 twist and do not like bullets above 62 grain.....it likes 40-55 grains the best.....FMJ bullets will rarely be as accurate as a higher grade HP, B-Tip or similar bullet.....go to the range and shoot...bad day shooting is always better than a good day working.......
 

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In terms of commercail ammo Mini (582 series ranch rifle) loves (groups best) Nosler 64gr Bonded, 62gr Federal Fusion & 2 different 62gr BT rounds.... It does fine with assorted 55gr FMJ (I've shot both 223 & 5.56 thru mine), just ok with 45gr JHP's and not so good with 40gr Vmax's (I assume it's because the tips are gettign distorted on the feedramp, causing them to yaw & tumble)

As for the Mini-14 and 223Rem vs. 5.56mm ammo quesiton; I'd suggest you read the section of manual that came with your gun that addresses "Ammunition" (pg 13 in the most recent version, that also happens to be availible for download on Ruger.com)
 

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The most accurate factory ammo I have found for my 5.56X45mm rifles are the Hornady 223 Rem 53 gr V-MAX Superformance or the Hornady 5.56 NATO 55 GR GMX Superformance. You can also try the Hornady 5.56 NATO 75 gr BTHP Superformance Match ammo. They also make .223 in 68 and 75 grain match ammo.
 

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The 1:9 twist barrel should shoot either 55gr or 62gr just fine. The weight of the bullet doesn't matter so much for stabilization as does the length of the bullet. Naturally, heavier bullets will be longer. And a BT will be slightly longer than a FMJ bullet. That is why you are hearing that FMJBT is not as accurate as plain ol' FMJ in a Mini-14. So, if you shoot bullets heavier than 55gr, maybe they should not be boat tail. But the only way to find out is to try it.

I haven't proved or disproved the theory, it's just what I've read on the forum. And,yes, the Mini-14 is chambered for 5.56 so you can safely shoot either 5.56 NATO or .223 Remington.
 

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As per answer by Ruger on their website:
Can I shoot 5.56 NATO ammunition in my Mini-14 or Ranch Rifle?
With the exception of the Mini-14 Target Rifle, which accepts only .223 Rem. ammunition, .223 Rem. and 5.56 NATO can be used in all Mini-14 rifles and Ranch Rifles.
Please note that "Military Surplus" 5.56mm NATO can vary greatly in its quality and consistency.
 

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drt4lfe,

Why???

Why is HP more accurate than FMJ? That has never made sense to me. Why is a bullet with a smooth solid point more accurate than a bullet with a hole in the front of it? I understand that BT bullets can be more accurate, but not HP.

That has always bugged me to hear that because I just don't understand and I have been shooting rifles since I was 10 and I am now 66. I guess I am stupid. But now that I think about it, I have never seen a HP 7MM Rem Mag or .30-30 or .30-06 but thousands of .22 HP and I have just bought some .223 HP which I have yet to shoot.

Bruce
 

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drt4lfe,

Why???

Why is HP more accurate than FMJ? That has never made sense to me. Why is a bullet with a smooth solid point more accurate than a bullet with a hole in the front of it? I understand that BT bullets can be more accurate, but not HP.

That has always bugged me to hear that because I just don't understand and I have been shooting rifles since I was 10 and I am now 66. I guess I am stupid. But now that I think about it, I have never seen a HP 7MM Rem Mag or .30-30 or .30-06 but thousands of .22 HP and I have just bought some .223 HP which I have yet to shoot.

Bruce
A center fire hollow point is not necessarily more accurate than a FMJ. But the HP ammo, especially in .223, is usually manufactured to a higher standard than FMJ, which is usually a plinking round. HP ammo is a hunting round and therefore calls for more precision in the manufacturing process, which leads to better accuracy. The exception would be target grade ammo. You will not see many shooting HP ammo in target competition. Everything else being equal, the FMJ round, or even a pointed soft point, will be more accurate than HP. That's my story and I'm sticking to it.
 

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I have got good accuracy from some FMJ's but not near as good as H.P. Match bullets. Match bullets like the ones from Hornady and Sierra are among the most accurate mass produced bullets ever made. And they are almost without exception, all hollow points. I believe it's because having the hollow cavity at the tip makes the bullet more base heavy, which contributes to better accuracy. I don't know of any H.P. Bullets that are "game" bullets, H.P.'s are either for target or varmints. Most bullets for hunting game are either soft points or a protected tip like the Nosler Ballistic Tips.
 

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A center fire hollow point is not necessarily more accurate than a FMJ. But the HP ammo, especially in .223, is usually manufactured to a higher standard than FMJ, which is usually a plinking round. HP ammo is a hunting round and therefore calls for more precision in the manufacturing process, which leads to better accuracy. The exception would be target grade ammo. You will not see many shooting HP ammo in target competition. Everything else being equal, the FMJ round, or even a pointed soft point, will be more accurate than HP. That's my story and I'm sticking to it.
No Long Range Competitors use ( Hollow Points ) ???? A HP cuts air better than a FMJ or soft point....Go to a Benchrest match and see if anyone uses FMJ.....you won't see any....you will see HP's....Why does Federal and so many other companies use HP's in all there Match grade ammo ??? All Federal Gold Medal Match ammo is HP....not FMJ or soft points.....Do some research and you will find HP's are the bullet of choice for target and long range shooting, are other bullets used ? yes.....see which is used the most....check out Berger Bullets, known as possibly the best long range bullets made.....HP's......
 

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I have got good accuracy from some FMJ's but not near as good as H.P. Match bullets. Match bullets like the ones from Hornady and Sierra are among the most accurate mass produced bullets ever made. And they are almost without exception, all hollow points. I believe it's because having the hollow cavity at the tip makes the bullet more base heavy, which contributes to better accuracy. I don't know of any H.P. Bullets that are "game" bullets, H.P.'s are either for target or varmints. Most bullets for hunting game are either soft points or a protected tip like the Nosler Ballistic Tips.
HP bullets are in my experience the BEST bullet made for deer and such.....Shoot a deer with a Sierra 168 BTHP out of a .308 or .06 and see what happens....and then say they are just for varmints and paper.....HP's of 150 to 190 grain will kill deer quicker than most any ( game ) bullet.....they expand and use all there energy very quickly on the animal.....if you do your part, animal never moves out of it tracks....all I use is 168 BTHP's for deer....and have never had to chase one down or shoot twice....
 

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IF FMJ bullets could be as accurate as HP's ? Surely one of the bullets makers would be making Match Grade FMJ bullets ? FMJ bullets will not perform with a HP even if both were built to same exact tolerances.....Laws of Physics prove so.....
 

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if your gun is chambered for 5.56 shoot 5.56. if it is chambered for .223 shoot .223
5.56 ammo can blow a gun up in your face if it was chambered to shoot .223.
read the stamping on your gun
 

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if your gun is chambered for 5.56 shoot 5.56. if it is chambered for .223 shoot .223
5.56 ammo can blow a gun up in your face if it was chambered to shoot .223.
read the stamping on your gun
As has been pointed out in the other thread on this subject you started, you are incorrect when it comes to the Mini 14 (with the exception of the target model.) For whatever reason, Ruger stamps "223" on the rifle while making it very clear in the owners manual that the gun can also safely fire 5.56. You are correct that a gun owner should always verify what caliber a gun can safely shoot but incorrect in this case to rely soley on the stamping on the rifle.
 

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A bit late but posted for clarification...

From the Ruger manual:

"The RUGER® MINI-14® RIFLES are chambered for the .223 Remington (5.56mm) cartridge. The Mini-14 Rifle is designed to use either standardized U.S. military, or factory loaded sporting .223 (5.56mm) cartridges manufactured in accordance with U.S. industry practice.”
 

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Someone never read the owners manual!

Someone never read the owners manual!
 
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