boat tail OR flat base for short range

[cjmac]

So with a 223 . Id like to use 52 smk , 69 Smk. Ill be loading for my bolt gun and AR-15 . iv picked these 2 bullets for both guns so i can just buy them in bulk. I only plan on shooting 300 yards max. So i dont think ill need a 77 gr. But im not sure if at short range such as 200 a flat base will preform any better than a boat tail... only reason i ask is that sierra makes a 53 FB .

 

[Dusty Stevens]

First off what twist? Limited on mag length. I use 75 bthp hornadys in a mag but thats a 7.7" tw. For a slower twist id use the 52fb.

 

[tcoz]

At short range it shouldn't make much difference whether you use boat tail or flat base. I use boat tail bullets simply because they're easier to seat straight.

 

[sbhooper]

At short range it shouldn't make much difference whether you use boat tail or flat base. I use boat tail bullets simply because they're easier to seat straight.

This. Just use the one that your rifle likes. Performance should be identical at short range.

 

[mikecr]

Likely depends on twist and barrel length.
I doubt it'll make any difference in an AR15.
I would try the FB in your bolt gun, especially if it's 14tw.

 

[cjmac]

Both are 1 in 7 twist. Boat tail is a LOT easier to seat that another reason i like them.

 

[Clint M]

I'm not nearly as experienced as many here, but my experience has been just the opposite from previous posters. Short range flat base will shoot better than boat tail, and most of my shooting was done with a 223. 52gr match bullets in flat base would shoot better groups than bt's, and 40gr v-max flat base were as accurate as the match bullets I tested Sierra 69gr hpbt, Sierra 52gr flat base (several Sierra bullets with load data from them, and purchased some other brands to compare). I tested this across three different guns, actually done a little bullet testing Sierra sent me some bullets this is when Cooper rifles had just started getting big on the net so they were interested as well. I had all this data I saved, but lost it on a hard drive crash.

 

[people]

Chamfer the mouth of your case if you are not already. That will help with seating. Other than that only your rifle's will tell you what they like.

You never know how a bullet will shoot. Sometimes cheaper just works.

 

[searcher]

With multiple .223's, I have always been able to get 69's to shoot far better in a 7 twist than the lighter bullets. Conversely, my 50-53 bullets always excelled with 1-14, 1-12 or even 1-9 tw on occasion - rarely good with 1-7.

 

[Dusty Stevens]

I like the hornady 75bthp in my 7.7tw. Seems to be a favorite among service rifle competitors and cheap

 

[bigedp51]

Those who fail to read history are doomed to repeat it.....

Flat base bullets reduce throat and bore erosion and are more accurate in a worn barrel.

The history

The British used cordite powder, a early double base powder in their Enfield rifles and flat base bullets. BUT cordite powder was banned from machine gun use and single base powders were used with "rebated boat tail bullets" to reduce bore erosion.

Moral of story, short range accuracy 300-400 yards flat base bullets are more accurate and seal the bore better. (obturate)

 

[BoydAllen]

I used to be of the opinion that short range accuracy belonged to flat base bullets. Since that time, I have learned a thing or two. The very first article that I had published in Precison Shooting (close to 20 years back) was really just a letter of inquiry as to why some barrels do not shoot BT bullets accurately. The editor turned it into an article, and that piece was mentioned in perhaps a half dozen articles, written by several other authors. The consensus among those that answered my question seemed to be that the issue was barrel quality, specifically whether the dimensions of the bore were sufficiently uniform from end to end. If they were, then BTs would perform well, and if not, they would be less accurate than flat base, presumably because they would be able to maintain their seal better in a bore of less than perfect dimensional uniformity, (specifically tight and loose spots).

In the last few years, in short range benchrest, there has been an increase in the successful use of BT bullets, and over the long haul, there have always been those who shot them well, including my friend Benchrest Hall of Fame member Gary Ocock, who has shot BT bullets that he has made, throughout his long shooting career.

What it all comes down to is that the only way to know if a particular rifle will shoot a particular bullet accurately (assuming suitable twist) is to test.

 

[bigedp51]

There is a reason why Lapua makes rebated boat tail bullets.....................

As stated before a flat base bullet will seal the bore better than a boat tail bullet.

And a flat base bullet will be less effected by the condition of the muzzle as it will with the high pressure gas pushing on the tapered boat tail upsetting its stability.

Boat tail bullets shoot best when they conform to bore diameter and produce a tight gas seal. And this explains the rebated boat tail design that the British military used and Lapua copied in their bullets.

All you need to do is recover your flat base and boat tail bullets and inspect the bearing surface of the bullets. When a flat base bullet is kicked in the seat of the pants it expands and seals the bore. And a boat tail bullet is less likely to conform to bore diameter due to the shape of the boat tail and how pressure works on its surface.

Those who fail to read history are doomed to repeat it.....

British .303 Mk.8z rebated boat tail machine gun ammunition below.

And the Lapua rebated boat tail bullet.

Question: What does a Walrus and Tupperware have in common?

Answer: They both like a tight seal.

 

[Richard Jones]

I would say that most short range BR folks use FB bullets, but as Boyd stated, others use BT's very well indeed. Didn't a Carmichel fellow set a BR record with BT's?

I don't shoot BR so can't swear to the above, just going by perusal of BR shoot equipment lists and the fact that it seems like the majority of BR custom bullets are FB.

At 300 and less, I doubt you're going to see much difference, if any.

In any case, feed it what it likes.

 

[bigedp51]

So with a 223 . Id like to use 52 smk , 69 Smk. Ill be loading for my bolt gun and AR-15 . iv picked these 2 bullets for both guns so i can just buy them in bulk. I only plan on shooting 300 yards max. So i dont think ill need a 77 gr. But im not sure if at short range such as 200 a flat base will preform any better than a boat tail... only reason i ask is that sierra makes a 53 FB .

Where did the OP say he was shooting benchrest and how many benchrest shooters use a AR15 rifle with a flash suppressor on the end of the barrel?

You benchrest shooters should be shot with a very dull blunt boat tail bullet in the groin.


Here endeth the lesson. .... :

 

[Richard Jones]

"Here endeth the lesson. ...."


Promise?

 

[bigedp51]

So with a 223 . Id like to use 52 smk , 69 Smk. Ill be loading for my bolt gun and AR-15 . iv picked these 2 bullets for both guns so i can just buy them in bulk. I only plan on shooting 300 yards max. So i dont think ill need a 77 gr. But im not sure if at short range such as 200 a flat base will preform any better than a boat tail... only reason i ask is that sierra makes a 53 FB .

cjmac

Forget the 52 and 53 grain Sierras and buy the green tip Z-Max Hornady bullets and shoot Zombies in the head with both rifles.

 

[bigedp51]

"Here endeth the lesson. ...."


Promise?

Did the OP post his question at Benchrest Central?

This website is Accurate Shooter and this is the Reloading forum (all calibers)

And "SOME" people need to read and follow the OP question.

 

[Shynloco]

Forget the 52 and 53 grain Sierras and buy the green tip Z-Max Hornady bullets and shoot Zombies in the head with both rifles.

cjmac,
Gotta go with Bigedp51 on this one. I load the 55's in my son's gas gun (AR15) and the Sierra 52 HPBT & 53 FB's in his .223 bolt gun. Tried reversing them and each rifle hated the other's bullets. Just my experiences.

Alex

 

[BoydAllen]

I have factory rifles that shoot both. The only way that I discovered this was to test, which was my recommendation. Ed get over yourself. All I said was to try whichever bullet he is curious about in whichever rifle he wants to know if it will shoot in. Back in the days when the first Colt Hbars came out, I knew a shooter who shot very nice groups with his with handloads with 69 gr Sierras. That was in a factory AR with a flash suppressor. In my post, I did not refer to anyone else's, or denigrate any opinion, just related my experience and some factual information. You might consider that in the future.