The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

HALODIN wrote:Yep OK it wasn't built for accuracy... it's built like my old C02 Brocock AR-12.

Unsurprising really as it's built by an airsoft manufacturer (Umarex)! :roll:

Also, I had to google what the C02 Brocock AR-12 was!

OK leave it with me.

HALODIN wrote:OK leave it with me.

Many Thanks! :)

Hi

The Spikes and CMMG's are all chambered .22 Sporting which is a sloppier chamber than the tighter Match version that the Raven uses.

The Bradley Arms guns and my Ravens are chambered .22 Bentz, which is about as tight as you can go on the chamber while still retaining functionality from a semi auto bolt.
You will also see many Volquartsen 10/22's etc chambered like this.

The tighter the chamber the more consistent the position of the round is, accuracy increases but it becomes increasingly difficult to automatically feed and cycle rounds.

The looser the chamber the easier it is to feed and cycle ammunition but accuracy suffers as the round can be positioned at differnt angles each time. When it is fired the bullet engages the rifling inconsistently and accuracy suffers.

For this reason a bolt action rifle is usually more accurate than a semi auto, as it is manually fed and can afford to have a tighter chamber due to the geometry of the bolt magazine and bore.

22 AR rifles have quite steep feed ramps due to space constraints, bolt guns not so. This makes feeding easier on a bolt gun than in an AR so the chamber can be tighter and thus more consistent too.
The semi auto 22 AR is also working on a blowback action so increased chamber friction from a super tight and more accurate chamber will scrub off energy and reduce the efficiency of the bolt causing potential short stroking etc....
Remember that at the time of extraction or 'blowback' in the semi auto the case is still expanding and pretty hot.

The bolt action rifle has non of these problems and the case has fireformed by the time the user is working the bolt.


As for accuracy then every barrel is different and therefore potentially requires different ammunition to function at its absolute best.

The Raven uses a martensistic stainless barrel made from LW50 steel by Lothar Walther in Germany. It's chambered .22Bentz and we dial indicate the bore runout down to .0002'' before running the reamer in, that has a live pilot on the end that fits the bore of the barrel exactly. The reamer is also held in a floating reamer holder just in case.

The chamber is cut with a cocktail of cutting fluids that contain sulphur and molybdenum, it works out at over £200 a gallon and is our own special mix. The chamber is then very finely polished.
What that means is that the chamber is cut absolutely concentric with the bore and the breech face is perpendicular too. The chamber is free from cutter chatter and super smooth while remaining the correct size as indicated by our print.
We have the reamers made for us with a couple of minor tweaks to the original design that we think improve the performance.

By contrast a Spikes or CMMG factory barrel is dialed in to .002''at best and feature a much looser sporting chamber as explained above.

Now remember that no matter how dilligent we are at threading and chambering we did not make the steel or drill the hole in the barrel, ream the bore, button rifle it and then stress relieve it.
We buy a profiled blank to work on, as do the majority of gunsmiths across the UK.
So consistency of manufacture at this level also plays an important part. AND EVERY BARREL IS DIFFERENT.

In typical tests our barrels deliver a single hole/ clover leaf at 50 yards and approx 1'' at 100. Some are slightly better some are slighty worse.
These are groupings I have shot myself and interestingly these were achieved with SK Magazine Ammo (500 rounds in a bean tin). The same gun grouped Lapua XACT at 4 inches at 50 yards!!

I know of a Border Cut Rifled barreled Raven that will single hole at 100yards. The owner has been through every brand of ammunition he could find until he narrowed it down.

IT IS ABSOLUTLY DOWN TO THE AMMUNITION.

A Spikes will out shoot a Raven if it's running ammo it likes and the Raven hates. One Spikes will shoot Brand X better than another, just the same as a Raven.

Has the Raven got the potential to be much more accurate that the Spikes if fed what it likes, then the answer is emphatically yes.

At 25 yards most guns are capable of tight groups, it's a level playing field and a relativly pointless test. Unless you are running Umarex etc... that simply dont group very well.
It's only at longer ranges where you start to see the differences.
Like a protractor, the farther away the wider the angle and the more a guns ability to consistently set up a round and have that round engage the rifling comes into play.

That's accuracy.

But you are also going to need consistent ammunition too, as powder burn rate, case size, bullet seating and nose dimensions etc... are all going to have a contributing factor.

Just to be clear. Ravens are no more fussy than the next gun and will shoot tight groups at short ranges with a good slection of ammo.
If you want to stretch its legs with specific ammo that it likes and take the time to test said ammo, then its got the capability to go much further than a Spikes or CMMG factory rifle for sure.

But if you want the best long range accuracy from a rimfire then get a bolt gun.

Great reply Paul. I suspect you're talking about R.M's Raven, coincidentally that's his rifle pictured next to mine on the previous page. Interestingly I've never managed a single hole with my Match 54 @ 100 yards, so that's putting the cat amongst the pigeons...

I know of a Border Cut Rifled barreled Raven that will single hole at 100yards. The owner has been through every brand of ammunition he could find until he narrowed it down.

AR15 wrote:Hi

The Spikes and CMMG's are all chambered .22 Sporting which is a sloppier chamber than the tighter Match version that the Raven uses.

The Bradley Arms guns and my Ravens are chambered .22 Bentz, which is about as tight as you can go on the chamber while still retaining functionality from a semi auto bolt.
You will also see many Volquartsen 10/22's etc chambered like this.

The tighter the chamber the more consistent the position of the round is, accuracy increases but it becomes increasingly difficult to automatically feed and cycle rounds.

The looser the chamber the easier it is to feed and cycle ammunition but accuracy suffers as the round can be positioned at differnt angles each time. When it is fired the bullet engages the rifling inconsistently and accuracy suffers.

For this reason a bolt action rifle is usually more accurate than a semi auto, as it is manually fed and can afford to have a tighter chamber due to the geometry of the bolt magazine and bore.

22 AR rifles have quite steep feed ramps due to space constraints, bolt guns not so. This makes feeding easier on a bolt gun than in an AR so the chamber can be tighter and thus more consistent too.
The semi auto 22 AR is also working on a blowback action so increased chamber friction from a super tight and more accurate chamber will scrub off energy and reduce the efficiency of the bolt causing potential short stroking etc....
Remember that at the time of extraction or 'blowback' in the semi auto the case is still expanding and pretty hot.

The bolt action rifle has non of these problems and the case has fireformed by the time the user is working the bolt.


As for accuracy then every barrel is different and therefore potentially requires different ammunition to function at its absolute best.

The Raven uses a martensistic stainless barrel made from LW50 steel by Lothar Walther in Germany. It's chambered .22Bentz and we dial indicate the bore runout down to .0002'' before running the reamer in, that has a live pilot on the end that fits the bore of the barrel exactly. The reamer is also held in a floating reamer holder just in case.

The chamber is cut with a cocktail of cutting fluids that contain sulphur and molybdenum, it works out at over £200 a gallon and is our own special mix. The chamber is then very finely polished.
What that means is that the chamber is cut absolutely concentric with the bore and the breech face is perpendicular too. The chamber is free from cutter chatter and super smooth while remaining the correct size as indicated by our print.
We have the reamers made for us with a couple of minor tweaks to the original design that we think improve the performance.

By contrast a Spikes or CMMG factory barrel is dialed in to .002''at best and feature a much looser sporting chamber as explained above.

Now remember that no matter how dilligent we are at threading and chambering we did not make the steel or drill the hole in the barrel, ream the bore, button rifle it and then stress relieve it.
We buy a profiled blank to work on, as do the majority of gunsmiths across the UK.
So consistency of manufacture at this level also plays an important part. AND EVERY BARREL IS DIFFERENT.

In typical tests our barrels deliver a single hole/ clover leaf at 50 yards and approx 1'' at 100. Some are slightly better some are slighty worse.
These are groupings I have shot myself and interestingly these were achieved with SK Magazine Ammo (500 rounds in a bean tin). The same gun grouped Lapua XACT at 4 inches at 50 yards!!

I know of a Border Cut Rifled barreled Raven that will single hole at 100yards. The owner has been through every brand of ammunition he could find until he narrowed it down.

IT IS ABSOLUTLY DOWN TO THE AMMUNITION.

A Spikes will out shoot a Raven if it's running ammo it likes and the Raven hates. One Spikes will shoot Brand X better than another, just the same as a Raven.

Has the Raven got the potential to be much more accurate that the Spikes if fed what it likes, then the answer is emphatically yes.

At 25 yards most guns are capable of tight groups, it's a level playing field and a relativly pointless test. Unless you are running Umarex etc... that simply dont group very well.
It's only at longer ranges where you start to see the differences.
Like a protractor, the farther away the wider the angle and the more a guns ability to consistently set up a round and have that round engage the rifling comes into play.

That's accuracy.

But you are also going to need consistent ammunition too, as powder burn rate, case size, bullet seating and nose dimensions etc... are all going to have a contributing factor.

Just to be clear. Ravens are no more fussy than the next gun and will shoot tight groups at short ranges with a good slection of ammo.
If you want to stretch its legs with specific ammo that it likes and take the time to test said ammo, then its got the capability to go much further than a Spikes or CMMG factory rifle for sure.

But if you want the best long range accuracy from a rimfire then get a bolt gun.

Thanks for the explanation, Paul.

Great reading and a lot of attention to detail in making the rifle.

Will send an email in to get an idea of costs...

Thanks again.

Thanks guys, no problem.

HALODIN wrote:Great reply Paul. I suspect you're talking about R.M's Raven, coincidentally that's his rifle pictured next to mine on the previous page. Interestingly I've never managed a single hole with my Match 54 @ 100 yards, so that's putting the cat amongst the pigeons...

I know of a Border Cut Rifled barreled Raven that will single hole at 100yards. The owner has been through every brand of ammunition he could find until he narrowed it down.

I've met R.M a good few times at CSR and he is a good shot. I know I'd struggle shoot a single hole with anything at 100 yards. Are we talking about a .223 Raven or does this refer to a 22lr?

I'm not surprised, he talks enough to have met everyone everywhere at least once... I suspect he is, he won our club CSR competition with an enfield he picked up a couple of days before. He lives and breathes shooting AFAIK.

I assumed we were talking about .22LR, but maybe not.

This is the rimfire forum and discussions should be confined to that subject.