TargetTalk

Hello TargetTalk members,

Does anybody know somebody converting a FWB 700 (Universal) to FT specs in the US?

I know that this is going to hurt many 10m shooters' ears and will raise many eyebrows but this is the intended use I have for this rifle; the P70 FT is no longer an option because it has been discontinued and most important because I already have the 700 universal.

Is there a velocity adjustment in this rifle to set it with a chronograph or does it require internal modifications?

Any advice? Anybody knows where could I get an assembly diagram?

Best Regards,

azuaro

I don't know about the adjustments to the velocity, but the P70FT has a different twist in the barrel rifling for the MUCH heavier pellets used in FT competition. Jacking up the speed on a match rifle will only provide you with a compromise, not a real FT rifle.

Just my opinion.

Marc

Hi
Mark is right, you will end up with a compromise. The field target rifles that are based on the 10m match rifles that some of the manufacturers offer have different barrels. These are designed with a different rifling twist to length ratio to give tight groups at higher velocity with the heavier field target pellets over longer ranges.
Also, if its possible to increase the volocity of the 700 to field target velocities, you may start to feel a slight kick on shot release as the stabilizer becomes less effective.

My guess is that your groups will open up rather than staying tight due to the barrel. Seek advice from your FWB dealer.
Get the right gun for the job.

Peepsight

Thank you for pointing this out Marc…

I reviewed both, the P70 FT and the 700 barrels and both have a 1:12 twist over a 12 groove barrel.

These similarities in barrel specifications confirm the theory that the stabilization of a projectile is based more on the length of the bullet than on its weight.

Barrel twist in order to keep the same stabilization is not going to vary significantly when you are increasing the velocity of a pellet from 570 to 750 fps. If we were talking about a firearm caliber going from 2,200 fps to 3,200 the story will be different...You would actually need less twist...

The Britain School of Sand Hurst from 1929 (has not changed in 78 years) established that in order to stabilize a projectile, the twist of a barrel is determined as follows:

Required Twist = 150 x square of the caliber in inches divided by the length of the projectile.

As an example: A .30 caliber bullet that is 1.35” long
150 x .09 divided by 1.35 equals 10 inches. This number is interpreted as 1 turn in 10 inches or a 1 in 10 twist.

In the case of a pellet: A .177 caliber pellet that is .21” long
150 x .03 divided by .21 equals 22.38 inches. This number means that 1 turn in 22 inches

More twist will put more spin on the bullet but this will not necessarily stabilize it better or make it more accurate. It will require more gases (air-CO2 or burn powder) to propel the bullet at the same velocity because there will be more friction (tighter twist).

In firearms the barrel twist has to be closer to what the formula says because a tighter twist will reduce velocity and a tighter twist will induce more barrel wear.
So, if you can stabilize a bullet with a 1 in 14” twist going to a 1 in 10” twist is not going to stabilize the bullet better or make it more accurate but it will for sure reduce the velocity and increase the wear inside the barrel.

Air guns (pistols and rifles) are not near as critical as firearms in this matter, as we saw in the pellet example: All you need is a 1 in 22” twist barrel to stabilize a Match pellet, and going to a 1 in 12” twist is not going to hurt much the velocity because of the inherent low initial velocities of air guns. Barrel wear caused by high velocity friction is out of the question in a pellet gun...

The reason why pellets tend to be less accurate at higher velocities is because their very low weight, this makes them more sensitive to changes in velocity. The lighter the pellet the more sensitive. This is another reason why you need more weight in a pellet when shooting higher velocities...

Most of the high end air gun manufacturers utilize the 1:12 twist, I have never seen a 1:10 or a 1:14 but I don’t mean that this can not exist out there because there is no technical reason impeding it. The reason they use this numbers is because of the synergy and expertise in manufacturing their firearms barrels more than anything else because wind deflection for a 10m inside shooting rifle is practically non-existent. This is another reason why the P70 has the same twist 1 in 12 twist, to spin the pellet more in order to help it with wind deflection from shooting outdoors.

For increasing velocity in an air gun the length of the barrel is important up to a certain point (same with firearms) then the diminishing returns law goes into effect. Both of the FWB rifles are about the same lenght...

These are the reasons why I don’t see that a 700 can not be turned into an FT gun by increasing its velocity from 570 to 750 or 800 fps. The only difference then would be sights, weights, and barrel tubes...Then you could have an adjustable rifle for two kinds of competition and adjusting the rifle for 570 or 750-800 fps would be a matter of using a chronograph.

So….If anybody out there has the assembly diagram for the 700 or knows how to adjust its velocity, please help all of us in this forum.

Thanking you for your reply, please receive my best regards.

AZ

Thank you for your observations Peepsight...

You or I will not feel the kick of an increase in velocity from 570 to 750 fps given the very low weight of the pellets, the insignificant increase in velocity and most important, because of the weight of the rifle.

If the stabilizer works at 570 fps, there is no reason why you can not adjust it to work at 750 or 800 fps...A stabilizer is not restricted to a fixed velocity or weight of a pellet, it is a matter of understanding how it works…

Very unfortunately, most of the FWB dealers are more interested in selling you another gun than in helping you to do what you want to do; at least this has been my experience in the US.

I am the kind of person who likes to fine tune a machine, whether it is a handgun, a rifle, a shotgun or a bow and utilize it for any kind of shooting, competition or hunting.

I have had very good results with this theory in the past with shotguns and bows...With the very same shotgun that I use for successfully competing in live bird competition in Central and South America (Beretta SO9 Custom with Brailey chokes), I shoot trap, skeet, hunt quails, and pheasants also very successfully…The same happen with my bow, I use it for indoor and outdoor competitions and for hunting.

I don’t see any reason why a machine can not be tuned for what you want it to do as long as it is technically possible, and what I am asking-suggesting for the 700 is possible. It is just that I don't know how to adjust the velocity on this model 700 and even though I am a mechanical engineer, I don't want to take it apart without an assembly manual in order to find out how it works .

Best regards,

AZ

You need to modify the regulator (change it) and make some modifications to avoid vibration due to the higher velocity. Either Alan Z or Korick can do it, they have done possibly hundreds of modifications to P-70's, Anschutz, Steyrs etc...Both are reliable and well known within the airguning community.

joekorick@attbi.com
Pneumatic Engineering
Joe Korick
3509 NW 132nd Circle
Vancouver, WA. 98685
Email: joekor@uswest.net
"The Precharge Specialist", Specializing
in pneumatic regulators for all
precharge applications.

Alan Zasadny
Antioch, IL
(847) 838-0187
Custom Stocks, airgun modifications
and accessories

Further information about the modifications or the tuners can be find at the James Kitching yellow forum (network 54).
Carlos

Any 10-meter AR are design for just that, 10-meter shooting. they are not design for FT or High power. Such as the regulator is not design for it, the barrel is too short and it twist rate is too high, plus other problems only a professional Airgun designer can tell us. For FT, you should be getting an FT rifle that was design for that purpose from the ground up. Try the HW-100. It has the best trigger (match trigger like) of any production FT that is out there, high quaility built, and deadly accurate.

Joe Korick mentioned above does just what you are looking for. Put his name into a search engine and you will find several good articles about what he does and has done.

Properly done you will have a fine FT rifle, but all elements must be integrated properly. As you have already posted, your barrel, receiver, sights etc. will be fine.

FABIAN and LEE,

Thank you so much for this valuable information....I will contact him ASAP.

Best Regards,

AZ

Azuaro,
I stand humbly corrected.

Good luck with your conversion to FT.

Marc

Thank you so much for your valuable input Marc...

The purpose of any forum (I think) is to discuss in a very friendly manner our needs and findings always respecting what other think or have experienced...

Any input is very valuable as long as it is analyzed and discussed properly because it illustrates other forum readers who might also be interested in the problem/findings as well as the members analyzing the situation.

I will be in contact with Joe Korick and Alan Zasadny and will be posting any further findings/modifications; I am sure that it can be done successfully but who knows, machines are sometimes very temperamental!

If anyone has a schematic for the FWB model 700, please let me know: azuaro@icehouse.net

Thanking you once again for helping in this problem, please receive my best regards.

AZ

pop along to airgunforum.net where it might be worth posting the question again...it has a dedicated FT section...another place to ask is airgunbbs.com ...both are uk based forums, but as the UK is the home of FT it tends to have more info on conversions.

you will need to adapt the reg, thats for certain to get you higher than 6ft/lb. Over here our legal limit is 12, but that aside most fell that guns shoot better around there than at higher powers anyway...we'll still be competing in the worlds this year with that power, and we'll probably go home with all the silverware ;)

you might find that if your gun has a stabiliser that might get junked as well, depending on how it performs with higher power.

i wouldn't be concerned about barrel specs...i think you'll find that the steyr and walthers have the same barrels on their FT and match guns, the shroud just being the difference, indeed the walther dominator barrel is somewhat shorter than the shroud indicates.

i might be wrong. The p70 and the 700 may indeed have different barrels...the p70, as with steyr 100/110, anschutz 2/8002/20, walther dominators is a popular route over here....things like hw100 are ok but you wont see many on the national circuit for a variety of reasons, usually because there is better kit out there.

a popular converted gun on the circuit is the anschutz 2002, which is converted by Dave Welham at Airmasters...the barrel doesnt get changed. Anschutz did do a 2020 which was 12ft/lb but not many made it into the UK. People have also successfully converted 8002's as well.

korick regs have a good rep over here as well.

generally the thought is that a 10m gun is a good basis, but that if the manufacturer has released a higher power version then that might be a better/cheaper place to start. But it doesnt stop there...most FT guns have more work done to make the reg even better, and then things added or removed to make them balance and handle better...its not uncommon to see rigs on the circuit where the only stock items left are the breech and barrel...

people often remove A clamps and fully float barrels, often junk the ally stocks in favour of something more akin to FT positions, add different hooks, change the reg, add different scope rails and play with internal gubbins until they're happy with it. Of course, there probably isnt a 10mFT variant that wont out shoot it's owner, but often consistency is affected by temperature etc which can affect its performance...a 10m range is quite a static enviroment compared to the conditions i've shot in this year which go from -4 deg C to 35 deg C, wind, rain & snow, dust sand...

and thats just the gun...then we get onto the scopes and pellets :D

Very valuable and useful information robf...Thank you!

no worries...i've been only shooting FT competitively for 18 months, so you will find more experienced opinion on those forums...but we're a friendly bunch so if you keep asking stuff you should be able to piece the picture together.

another thought is just getting another gun, there are other dedicated FT rigs out there like the dominator or steyr 110...as you have korick over there he can do you a bomb proof reg for the walther which is probably the only aspect i'd recommend looking at. Over here the steyr dealer sorts the LG's out before dispatch and steyr have been pretty quick to remove the update's glitches...accuracy as ever with all these is excellent, my friend's lg110 has a test group that is about 7mm edge to edge at 50m.

but if your fond of the feel of the fwb then i can see that being a strong argument...i like the feel of my walthers, but my anschutz doesnt feel quite the same, so one day i might treat myself to a carbontec :D