Remington .223 twist rate

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squirrelshooter

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I’ve got a Remington 783 in an Oryx chassis I’ve been working on building up some hand loads for and had completely given up on the 68 grain bullets I’ve been working with. The bullets were all keyholing badly. I thought I needed more velocity, so I kept bringing up the charge weight, tried different powder, still no luck. Finally tonight I noticed a search result on google where a fellow checked his twist rate and found it was 1-14 instead of the advertised 1-9. Well, it looks like I’m in the same boat! That explains the keyholes! Anyone else run into this? I’m guessing I’m not going to get any support from Remington nowadays!
 
I was having the same problem. Found out short 52 grain bullets work great in it with hand loads . This explains why try the short lighter bullets if it's anything like mine you'll get great results. Unless you want to shoot the heavy bullets. Then I would order an IBI barrel in the twist rate you want . I have given up of firearms warranty in Canada.
 
Barrel twist can vary slightly as I understand it, that said, 68 grain match (assuming Hornady) may not stabilize in a 1 in 9, especially at lower altitudes/cold weather. If you are looking to shoot past 300-400m 75 gr Hornady Match will stabilize better, under 400m 53-55 gr flat base projectiles like the 55 gr V-Max.
 
redshooter said:
under 400m 53-55 gr flat base projectiles like the 55 gr V-Max.
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If indeed your barrel has a 1-14 twist rate, the above should work in your Rem 783. I have done load development in a 1-12 barrel and 55gr Berger Target and 55gr Hornady VMax (both flat base) performed much better than 52gr Sierra Match Kings (boat tail). The 1-14 twist rate is basically for lighter, fast moving bullets, for varmints.

HeliMD said:
Then I would order an IBI barrel in the twist rate you want .
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If you want to shoot the heavier bullets and stretch out the .223 then I second the above. The Rem 783 is a decent (and inexpensive) receiver to build on, and since you already have an Oryx Chassis.........
 
squirrelshooter said:
I’ve got a Remington 783 in an Oryx chassis I’ve been working on building up some hand loads for and had completely given up on the 68 grain bullets I’ve been working with. The bullets were all keyholing badly. I thought I needed more velocity, so I kept bringing up the charge weight, tried different powder, still no luck. Finally tonight I noticed a search result on google where a fellow checked his twist rate and found it was 1-14 instead of the advertised 1-9. Well, it looks like I’m in the same boat! That explains the keyholes! Anyone else run into this? I’m guessing I’m not going to get any support from Remington nowadays!
Click to expand...

Interested in knowing how he identified twist rate.
 
I’ve got some 40gr vmax to try. I’ll switch my focus to light bullets. Maybe try some 50’s as well. I recommend checking the twist on any 783 in .223 you might have though, may not be what it’s supposed to be!
 
redshooter said:
Barrel twist can vary slightly as I understand it, that said, 68 grain match (assuming Hornady) may not stabilize in a 1 in 9, especially at lower altitudes/cold weather. If you are looking to shoot past 300-400m 75 gr Hornady Match will stabilize better, under 400m 53-55 gr flat base projectiles like the 55 gr V-Max.
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The bearing surface measures the same between the Hornady 68 & 75 Gr HPBTs, so if one stabilizes so will the other
 
beltfed said:
The bearing surface measures the same between the Hornady 68 & 75 Gr HPBTs, so if one stabilizes so will the other
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Overall bullet length matters, not bearing surface length. Which is why, counter-intuitively, the 68gr HPBT (0.987" long) will be less stable then the 75gr (0.981" long), all else being equal.

That being said, both are marginal in a 1-9" twist.
 
beltfed said:
The bearing surface measures the same between the Hornady 68 & 75 Gr HPBTs, so if one stabilizes so will the other
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Length vs. mass is not the same, nor is the bearing surface for that matter, at least not in my ref., according to Mr. Litz the 75gr. Match will stabilize better than the 68gr.

My experience with 68 gr Hornady Match has been a very good load went to #### in -10c or colder. Several years down the road I get Applied Ballistics, and the data confirms my results.
 
Alpheus said:
Overall bullet length matters, not bearing surface length.
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I don't think so. I think you are confusing the ballistic coefficient with the barrels ability to stabilize the bullet at any given velocity.
In the context of this discussion, ballistic coefficient is irrelevant.

As a general rule, longer bullets have a longer bearing surface, but that isn't always true.
Take the Hornady's .224 offerings in the 75gr. AMAX and the 75gr. HPBT. The Amax is a longer bullet overall, but has a shorter bearing surface.
Some have reported that a 9 twist will stabilize the Amax, whereas they have issues spinning the BTHP.

There are plenty of articles all over the 'net that cover it.
 
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redshooter said:
Length vs. mass is not the same, nor is the bearing surface for that matter, at least not in my ref., according to Mr. Litz the 75gr. Match will stabilize better than the 68gr.

My experience with 68 gr Hornady Match has been a very good load went to #### in -10c or colder. Several years down the road I get Applied Ballistics, and the data confirms my results.
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No, length and mass are not the same - we agree on that point.
The bearing surface on the 68 and 75 gr HPBT that Hornady produce are the same, and for all intents and purposes should stabilize with the same barrel. The caveat to that is the other factor required for stabilization - velocity. If velocity is marginal at any given range with that particular barrel, then you may see a dip in performance as the bullet looses velocity, as it sounds like you did when you tried a given load in colder temps.

Also, it is plausible that we are talking about apples and oranges - insofar as the the 75 gr. 'Match' bullets - I'm not sure if the old AMAX is the same as the ELDs they produce now, but the Amax and BTHP of old were very different bullets and their only commonality being the weight.
 
The 69gr. Sierra Match King is a good starting point. Roughly measuring the bearing surface from the back of the boat tail to the start of the ogive is ~0.35", and they are advertised as optimal in a 7 to 10" twist barrels.
My personal experience with their use in Sig Classic greens with 10" twist barrels saw them working to at least 300m, and with some rifles, to 500m.
A 1 in 9" should have no problems with them.

Incidentally, the 68gr. Hornady BTHP measures ~0.45" and the 77 SMK around 0.5"
 
beltfed said:
I don't think so. I think you are confusing the ballistic coefficient with the barrels ability to stabilize the bullet at any given velocity.
In the context of this discussion, ballistic coefficient is irrelevant.
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I don't know why you think I am talking about BC in what I said, because I clearly am not. BC does not affect if a bullet will be stable in a particular barrel, at a particular velocity. But BC is not completely irrelevant when talking about stability, since an under-stabilized bullet will have a reduced BC.

beltfed said:
As a general rule, longer bullets have a longer bearing surface, but that isn't always true.
Click to expand...

Yes.... I just provided an example of that....

beltfed said:
Take the Hornady's .224 offerings in the 75gr. AMAX and the 75gr. HPBT. The Amax is a longer bullet overall, but has a shorter bearing surface.
Some have reported that a 9 twist will stabilize the Amax, whereas they have issues spinning the BTHP.

There are plenty of articles all over the 'net that cover it.
Click to expand...

How are these articles determining the stability of the bullets? Can you link to a few of them?

And once again, bearing surface length is effectively irrelevant to bullet stability. Neither the Miller or Greenhill formulas use that dimension.

Theoretically, the bearing surface length is a part of the total mass distribution of the bullet, but the further the mass of the bullet is away from the centre, the greater the effect it has on stability. Hence the importance of overall length and complications with flat base and polymer tip bullets.

Reference your experience with Sig Classics, how are you determining that they are "working"? Fully stabilized bullets do not necessarily correlate with small group size.
A .224 75gr Hornady HPBT going 2750fps in a 1-9" twist will have marginal stability. That does not mean it won't group well. That does not mean it will tumble. What is does mean, however, is the BC is being depressed by about 2%.
 
Well, a contentious issue for sure.
Without diving down the Rabbit hole that I know this is, I will say this:

Most of that belief was cultivated over more than a decade of shooting service rifle, and paying attention to what worked with the USAMU and readings of the Competitive AR15 amongst other publications, and knowing what worked with the AR15 and Sig Pe-90s, shooting everything from 50gr to 90 gr .224 bullets.
It looks as though what I thought was a widely held belief isn't, or at least isn't any longer, or perhaps is no longer 'de rigueur'

While both the Miller and Greenhill formulas are well regarded and I won't dispute them, they are not the axiom some profess them to be.

Anecdotally, the Sig would shoot a 69gr. smk fine to generally ~300m and show indications of loss of stability (exponentially larger groups and obliging) at ~400 and some would be key holing at ~500. So those are for the most part 10 twists (there are 7s too, but less in the wild). Any 9" twist barrel I've seen hasn't had issues.

The ability of the 75 amax (which sit at around 1.09" oal) to utilize a slower twist barrel than a 69smk that is considerably shorter at 0.9" oal is an example of disputing the oal of the bullet as a primary means of determining twist, at least imho.
 
Interesting topic, I suppose I'll pull out my "9-twist" Rem 700 and measure the actual twist rate and then compare to my notes. I'm shooting mostly the 69gr Sierra Matchking, but have put a box on 75gr Hornady Superformance Match through it "just to see" and it was very accurate at 100m.

Not sure if the extra juice from the Superformance load gave it a bit more stability but I'd love to fire off more of the 75's if I can dig some up.
 
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